In the United States, effective 2009-02-17, most television stations are required by law to cease transmitting analog TV (NTSC) signals and transmit only digital TV (DTV or ATSC) signals. This allows the spectrum currently wasted by simultaneous analog and digital transmissions to be reclaimed. Some low power stations may continue tohttp://www.tigerdirect.com/applications/SearchTools/search.asp?page=2&cat=1427&keywords=ATSC%20tuner&sort=Weight%20desc broadcast analog signals. Some stations will not wait until the 2009 deadline to switch. Newer stations are already limited in their ability to simultaneously transmit digital and analog signals and thus have trouble competing with other stations which are allowed full HDTV broadcasts and may switch over to digital only transmission sooner. For example, Charlottesville, VA had only NBC and PBS until a new broadcaster added ABC, CBS, and FOX; they have announced their intention to switch over before the deadline. Analog TVs will require a converter box to receive over-the-air television broadcasts after the switchover. Cable subscribers will usually not need one. Satellite subscribers will not need one if they receive their local stations via satellite instead of via an antenna. At least until 2012?
In order to ease the transition, the government is subsidizing the cost of converter boxes in the form of up to two $40 coupons per eligible household, with a limited total number of coupons. They began taking applications online on 2008-01-01. Apply today, using the link below, if you haven't already in case they run out. The budget should allow for about 37 million coupons but there are reportedly 70 million sets in use. More specifically, there are 22.25 million coupons which will be followed by 11.25 million which are restricted to homes with no satellite or cable. As of June 2008, over 15 million coupons had been ordered, almost 14 million mailed, and only 2.3 million redeemed, and the wer going at a rate of 100,000 coupons a day, thus the unrestricted batch of 22 million will be exhausted about Aug 2008 and the remaining restricted ones a few months after that. . In order to limit the subsidy to broadcast TV recipients, they have imposed some serious constraints on what the converter boxes can do. In an attempt to make the coupon eligible converter boxes unusable for HDTV upgrades, they have imposed constraints that may interfere with even broadcast TV use and have adverse affects on consumers and the environment. Coupon Eligible converter boxes will not have features you would expect on a fully functional standalone HDTV/DTV tuner box.
A converter box will not upgrade your TV to HDTV. You will be able to receive SDTV, EDTV, and HDTV broadcasts but they will all be displayed in standard definition (the resolution of old analog TVs), down converting where necessary. The display quality will not be as good as a low end SDTV digital TV, which while it may have the same resolution as an analog TV looks better because it can use progressive scan instead of interlacing. You will get a few additional benefits including an on screen program guide and the ability to receive additional subchannels. A TV station can divide its bandwidth among several subchannels, broadcasting up to one HDTV program plus lower resolution programs. However, these benefits will be offset by the inability to record programs and watch them at the same time without a second box. Another problem with recording is that your VCR or DVD recorder will probably be incapable of changing channels on the converter box making programmed recording difficult. Even recorders which have an IR sender for changing cable box channels probably won't know the right codes to send for converter boxes. TiVo may upgrade their software to do this. Some DVD recorders can accept software updates on DVD, but you will have to order the updates or download and burn them in the unlikely event that they are available.
With the desire to limit the coupon eligible converters to use with existing sets and following the self-serving advice of HDTV tuner manufacturers, many owners of high end analog TVs were left high and dry. If you have an analog TV with RGV, component (YUV), or VGA inputs or purchased a computer monitor with an analog TV tuner, presently use a TV tuner for a video monitors, you will be limited not only to SDTV resolution but also to composite video. Since CECBs are limited to SDTV resolution, there was absolutely no reason to limit the output to RF and composite. Further, some of these sets are capable of more than SDTV resolution since they double as computer monitors. Thus, these users will need more expensive ($180+) HDTV tuners to take advantage of their existing displays.
You may need to upgrade your antenna to receive digital broadcasts. Visit AntennaWeb for more information.
One would hope that some manufacturers will design coupon eligible converter boxes as subsets of a more flexible design, with optional components omitted to meet coupon eligibility requirements. Many households may require more converter boxes than they are allowed coupons for and they should have the option of paying a little more for a more flexible box, still benefiting from the economy of scale of the converter boxes.
You will generally need one converter box for each analog TV used to receive over-the-air broadcasts. In addition, you may need additional devices for VCRs, DVD recorders, and DVRs (TiVo, etc) to permit recording a show at the same time you are watching one, but these devices may not be capable of instructing the converter to change channels. Once you install a second converter, however, you are likely to encounter a fatal design flaw: the lack of unit codes on the remote to enable you to use either a single remote or two separate remotes to control the converter boxes individually. Thus, you will probably have to purchase, and learn how to use, two separate brands of converter box or resort to kludges like covering the remote control receivers to select the device you want to control.
Converter boxes will add to system complexity and user confusion.
Most coupon eligible converter box purchase will probably occur around the second quarter of 2008. The government won't ship the coupons till manufacturers are ready to ship the products and consumers will have 90 days from then to use the coupons. Anyone who didn't apply for a coupon by then, probably won't get one as the supply is limited.
Decode all standard ATSC digital TV formats: require
On screen Program Guide: PSIP required, other formats permitted
Tuning range: channels 2 through 69 required even though 52-69 are being phased out but may still be used by low power stations or needed during transition.
Sub-channel tuning: required. DTV can send more than one video program on the same signal.
RF (antenna)Input: required, 75 ohm female F connector
Smart antenna input: permitted. The single RF antenna input may be used with an automatic external selector to select more than one antenna beam or control an adaptive array.
Antenna Analog Pass through or bypass switch: permitted.
300 ohm antenna input or adapter: permitted
Composite video/stereo inputs: prohibited? Final ruling doesn't say explicitly but earlier version appears to exclude. Passthru on those inputs?
AV Outputs
RF (antenna) output: required, 75 ohm female F connector
Stereo over RF output: permitted. Usually omitted to keep costs low under the premise that stereo tv's usually have A/V input.
SAP (secondary audio) over RF output: permitted. Note that DTV uses a system other than SAP and a converter may let you select secondary audio channels via the converter box menu instead of via your TV menu. No converters are likely to actually convert Digital SAP to analog SAP which is sent to your TV set over the RF modulator – they don't even provide stereo (2 channels), let alone 4 channels, due to the cost of dolby encoder chips and you would not be able to encode SAP over RCA plugs. Instead, you use the CECB remote to select which single audio program is sent to TV.
300 ohm antenna output or adapter: permitted
Composite Video + stereo audio outputs: required, RCA connectors
Composite Video + stereo audio inputs with passthru (required for daisy chaining): ???
S-Video output: permitted
S-video passthru input (for daisychaining): ?
Component video outputs: prohibited
VGA output: prohibited
RGB output: prohibited
DVI: prohibited
HDMI: prohibited
USB port. A USB port could be used for three functions
Streaming video output: prohibited
Software update: FCC allows software update (but no mention of USB?)
Remote control. Some TiVos have USB ports, as do computers with NTSC tuner cards used as TVs
IEEE-1394/iLink/Firewire video output: prohibited
Ethernet video output: prohibited
IEEE-802.11/Wifi video output: prohibited
Closed Captioning: required
Emergency Alert System (EAS): required
Parental Controls (V-Chip): required
Remote Control: required, batteries required.
Programmable remote which can control TV or other devices: permitted
Energy Standards
2W maximum power in standby: required
Automatic standby after 4 hours inactivity: required, user override required
Energy star compliance (1W standby, 8W operate): encouraged
LED power indicator: required
AC operation: permitted
DC operation: permitted
Battery operation: permitted
Switched power jack for TV: not mentioned in ruling. Remote control may be programmable to control TV power and volume.
Note that some units may have a power input jack and require a separate purchase of a DC adapter.
Accessory cables:
RF (antenna) cable for connection to TV: required
Video/Left/Right AV cable (RCA): permitted
Signal Strength Indicator (onscreen): required
Other signal quality indicators: permitted
Other functions
Video display: prohibited (TV's don't qualify)
playback: prohibited (DVD/HD-DVD/blueray players don't qualify)
Built-in Recording capability: prohibited (DVD recorders, DVRs don't qualify)
Software updates (over the air): permitted
16:9 widescreen: center cropping and letter boxing required.
Signal quality standards: see DTIA technical appendix
Programmed channel changes, for recording: not mentioned in ruling, or in product information.
AC/DC operation: permitted
Not responsible for errors. Use this table for initial evaluation but be sure to check manufacturers specs to confirm details. If it a feature isn't advertised it is assumed to be absent. Compiling this table is difficult as only sketchy information, if that, is available for most of the products. Some of the companies are so nebulous they don't even seem to have a web site. Much of this info was collected before units hit stores. Even after they are in stores, the online documentation for them is shamefully poor. This table was originally prepared before any of the products hit the market using what I could glean from articles, pictures, and the rare user manual and before other comparison tables were published by others.
This table lists only those features which are not required. That includes accessories. For example, one vendor lists a remote control, A/V cable, RF cable, User manual, quick start guide, and battery for the remote. The government requires the RF cable, remote control and battery, and user manual so only the A/V cable is listed as an accessory.
Shrinking the page (Control '-' in firefox), enlarging your browser window, or printing at a reduced size will let you see more of the table at one time.
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Brand |
Model |
CECB |
Pass thru |
S- Video |
Smart Ant. |
SAP |
Power |
Programable Remote |
Software Updates |
Supplied Accessories |
Menu Languages |
Front Panel Buttons |
DTVCC EIA-708 |
Other |
Retailers |
Reviews, Manuals, Videos, etc. |
Brand |
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Zenith Insignia (LG owns both) |
Yes |
No |
No |
No |
Yes |
Energy Star <1W/<8W AC only
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Universal |
No |
A/V cable RF push on cable (Insignia) |
English Spanish French |
Power CH+? CH-? |
yes |
EPG (now/next), zoom, letterbox, sleep, signal meter (with audio), SAP, close caption, recall |
Circuit City (Zenith) $60
Best Buy (insignia) $60 |
[hdtvexpert] [EPG pics] [DTT900 Manual] [DTT900 Video Review] [DTT900 video] [NS-DXA1 CC video] [NS-DXA1 manual] |
Zenith (LG) Insignia |
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Zenith Insignia (LG owns both) |
Yes |
YES |
No |
No |
Yes |
Energy Star <1W/<8W AC only
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Universal |
No |
A/V cable RF push on cable (Insignia) |
English Spanish French |
Power CH+? CH-? |
yes |
EPG (now/next), zoom, letterbox, sleep, signal meter (with audio), SAP, close caption, recall |
Circuit City (Zenith) $60 |
Zenith (LG) Insignia |
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TB100MW9 TB100HH9 TB100MG9 |
Yes |
No on MW9 Yes but clunky on HH9, MG9 |
No |
No |
Yes |
120VAC 1W/8W |
No |
No |
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English Spanish French |
No power or channel buttons |
yes |
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Walmart ( Kmart (philco) Sears ( Sams $44 (magnavox)
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[EPG pics] [TV100MW9 review] [TB100MW9 Channel Change Video] [TB100MW9 manual] [TB100HH9 manual] [TB100MG9 manual] |
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DTA800 (three models with significant differences.A is zoran based, B is broadcom, and B1 adds passthru but suffix is usually omitted.) |
Yes |
DTA-800B1 only
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Yes |
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Power CH+ CH- |
yes |
Can't manually add channels |
Listed on Walmart website for $50 but not sold in stores or online. (West?) |
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GE/Jasco (plastic) Goodmind(metal) |
Yes |
No |
No |
Yes (GE antenna only?) |
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yes |
Full Program Guide, goofy enclosure |
Target $55 |
GE/Jasco (plastic) Goodmind(metal) |
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VENTURER (unusable web site) Winegard |
Yes |
No |
No |
No |
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Power CH+ CH- |
? |
EPG: Current program only?
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Target $50 |
VENTURER (unusable web site) |
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DTX9900 |
Yes |
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RadioShack ($60) |
[EPG pics] [DTX9900 chan change video] [DTX9900 EPG Video] |
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DigitalSTREAM |
DTX9950 |
Yes |
YES |
No |
Yes??? |
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RS-232 |
RF Cable AAA batteries |
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RadioShack ship-to-store ($60) |
DigitalSTREAM |
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Brand |
Model |
CECB |
Pass thru |
S- Video |
Smart Ant. |
SAP |
Power |
Programable Remote |
Software Updates |
Supplied Accessories |
Menu Languages |
Front Panel Buttons |
DTVCC EIA-708 |
Other |
Retailers |
Reviews, Manuals, Videos, etc. |
Brand |
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Brand |
Model |
CECB |
Pass thru |
S- Video |
Smart Ant. |
SAP |
Power |
Programable Remote |
Software Updates |
Supplied Accessories |
Menu Languages |
Front Panel Buttons |
DTVCC EIA-708 |
Other |
Retailers |
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Channel Master MAG AVION |
CM-7000 CCB7707?? ATB7707??? |
Yes |
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Yes |
No |
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120VAC 8W/2W |
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Power CH+ CH- |
12 hour program guide |
Online $80 |
[review] [EPG pics] [review] [CM-7000 manual] [MAG CCB7707 Manual] [ATB7707 manual] |
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TR-40 |
Yes |
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June 16th SolidSignal: $52 |
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TR-50 |
NO DVR |
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DVR,Component output, ethernet, USB |
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APEX |
DT250 |
Yes |
Yes |
Yes |
Yes |
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multiple |
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3-Day program guide, DigitalCC, Volume control |
August |
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AMTC Alpha Digital RJTECH Tivax Mustek AccessHD AccessHD |
AT-2016 AT-2016 RJ-900ATSC STB-T9 MAT-K50 DTA1010D?? DTA1010U?? |
Yes |
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No |
Yes |
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RS-232 |
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Power CH+ CH- |
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DT1001 |
Yes |
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FT300A |
Yes |
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No |
No |
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Wall Wart Energy Star? |
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No |
A/V Cable |
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Power |
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Sansonic |
FT300RT |
Yes |
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Philco |
TB100HH9 |
Yes |
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MicroGEM |
Yes |
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DC input Wall wart? |
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Power Ch+ Ch- |
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MaxMedia |
Yes |
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Power Ch+ Ch- |
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DTA1000 22729 |
Yes |
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yes |
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CASTi |
CAX-01 |
Yes |
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AccessHD |
DTA1010D |
Yes |
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AccessHD |
DTA1010U |
Yes |
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LTA-260 |
Yes |
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Lasonic |
LTR-260 |
Yes |
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Artec |
Yes |
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No |
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12V Dcd 4W max AC wall wart |
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Multi language |
Power switch (poorly located on top) |
“Service port” Freeze frame |
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Micro Prose |
Yes? |
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YEs |
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A/V cable |
3 languages |
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Daewoo |
DAC-100 |
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D2A1D10 |
Yes |
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Yes |
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Yes? |
9VDC |
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D2A1D20 |
Yes |
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DigitalSTREAM |
?? |
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Yes |
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Brand |
Model |
CECB |
Pass thru |
S-Video |
Smart Antenna |
Secondary Audio |
Power |
Programmable Remote |
Software Updates |
Supplied Accessories |
Menu Languages |
Front Panel Buttons |
Other |
Retailers |
Reviews, etc. |
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Sylvania |
6900DTE |
NO HDTV |
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Yes |
Yes |
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Power CH+ CH-
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High def, DVI-D/HDCP, S-video, Component out, digital audio |
$90 used ebay |
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Samsung |
DTB-H260F |
NO HDTV |
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Yes |
No |
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Power |
HDMI, s-video, component, composite, USB (maintenance), NO RGB |
Typically around$169, can be found for $80. |
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Samsung |
SIR-T451 |
NO HDTV |
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DVI, RGB, component |
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Samsung |
SIR-T150 (discontinued) |
NO HDTV |
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Yes |
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RGB/VGA, composite, component, S-video, digital audio NO HDMI/DVI |
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Tivax |
LX1000 |
NO HDTV |
|
yes |
Yes |
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HDMI, compnent, composite, s-video |
$90 new
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Note: sansonic has two products listed with government but only one datasheet which does not specifically identify a model number, so features were attributed to the FT300A.
Rumor has it that Walmart is carrying the RCA model in the west and the Magnovox in the East.
This table doesn't list johnny come lately models.
There is a comparison table with many more models at Wikipedia
holl_ands on avsforum has done extensive work on comparing boxes. CECB Feature List (avsforum registration required). zipfile link has been setup by someone and is updated to point to the latest version when holl_ands posts a new one.
Many readers are no doubt hoping for a quick answer, a list of boxes that is very likely to satisfy their needs. Unfortunately, that list has zero members. Even within the constraints imposed on these boxes, there is not a single box on the market that will satisfy the needs of all users. I don't even think there is a single box that will perform well regardless of your A/V setup. You wan't to know which is the best? Try asking which is the least crappy instead. And unfortunately, the answer to that depends on your particular system requirements.
If you have a standalone TV with no other attached devices such as VCR, DVD recorder, DVR, cable/satellite box, DVD player, or video games, don't use secondary audio or closed captioning, and don't expect digital TV features like a halfway decent electronic program guide and don't even expect the picture quality you would get on a standard definition digital TV, and have good TV reception, don't use it in emergencies, don't need stereo audio on a TV with no external A/V input, don't need to re-aim your antenna to get different channels, don't have a TV with progressive scan, don't need to receive any analog channels unless you have spare A/V inputs on your TV or VCR, and don't expect any of this to change between now and when you upgrade to a digital TV and can live without firmware upgrades (bug fixes) and aren't concerned aout whether the box will last as long as your TV does, then any of the converter boxes available will probably work for you. If these conditions are not true for you, then some or all of the converter boxes on the market may prove inadequate or marginal. If your have a spare A/V input on your TV or video recorder, then your chances of living with a bare bones unit are a bit better.
If your VCR blinks 12:00 because you don't set it, you are confused by TV/VCR switches, are confused by the difference between changing channels on a TV vs changing them on a VCR, don't know which remote to use, etc. then the added confusion from having adding another box may be an issue for you.
Reasonable expectations include:
Not to lose any capabilities you had under analog TV
Not to have to purchase additional hardware to integrate into your system.
To have the features you would expect on a standard definition digital TV but in a more cumbersome package with more boxes, more remotes, and a bit more confusion.
Ability to control at least 3 converter boxes, maybe 4, of the same brand in the same room without remote control codes conflicting. If you have a TV with picture in picture and a VCR, DVD recorder, or single tuner DVR you may need 3 converter boxes just to regain the ability you had before. There should be a button or switch to select unit number. I have yet to see a single unit that provides this. You can partially work around this by taping a flap of paper or cardboard over each sensor and manually moving them.
If you record one show on your VCR/DVD-R while watching another you will require two converter boxes and you may encounter cabling problems unless your TV has three inputs (one for a converter box, one for the VCR, and one for DVD player). If you make unattended recordings, you a pretty much screwed unless your VCR (or similar device) has an IR blaster for controlling cable boxes. Only one box (TR-40) has even been announced that claims to offer a timer recording mode that will automatically turn the device on and select the appropriate channel at a preprogrammed time; even with this box, it is not clear how many programs are supported and you will need to program both the box and the VCR.
Many consumers will purchase a box and it will appear to work ok at first and then find out they are screwed when they decide they want to make an unattended recording, add a DVD player, etc.
To minimize consumer confusion, the government should have defined minimum standards for two levels of box:
The marginal box ($40). Minimum features currently allowed by law.
The adequate box ($60). Has all the features allowed by law and some they forgot to allow. Full Program Guide, VCR timers, S-Video input and output with passthru, Analog RF passthru, A/V (RCA) passthru, 12VDC and 110VAC power inputs, SAP, EIA-708 captions, front panel controls, software update, external channel change, unit codes on remote, smart antenna, 480p output, etc.
The deluxe box ($100+) or HDTV tuner, excluded from coupon. Adds high definition, HDMI/DVI/Displayport output, VGA output, component/RGB output, and passthru on all outputs. Digital audio output. May have Ethernet or USB slave connectors for use as a computer TV tuner. May have one or more USB host port for use with a flash memory (photo album, software upgrade, etc.) or for use with a hard drive to turn the box into a DVR. May have an internal hard drive or the ability to add one.
Manufacturers could produce boxes in between but retailers would carry at least one box that meets the adequate box specifications that would work in 99% of typical system setups without the need for additional hardware (except maybe a few cables) since it can daisy chain and provides all capabilities except simultaneous recording or picture in picture which require a second or third box.
And, quite frankly, they should have been honest and made the coupon worth $60-70 and allowed many more per household. Because that is what it is really going to cost consumers. They are getting money ($20 billion?) from auctioning off the airwaves and that money really belongs to the consumers who are affected, not the government. A typical household with 4 people, three bedrooms, a kitchen, a living room, and a rec room, 2 VCRs, and one TV with PiP may require 9 converter boxes.
The most interesting units ship to (online) stores/online retailers after the first coupons expire. Those are the apex DT250 and the Echostar DTVPal TR-40. The DT250 would be a good companion for the TV and the TR-40 a good companion for your VCR/DVR/DVD recorder.
The Zenith ZTT900 or the Insignia DXA1 (reportedly the same unit, LG owns zenith) looks like the most available model at local big box retailers, but don't get one manufactured before April to avoid the left channel audio bug. No analog passthrough, though there is a DTT901 model that isn't available locally that does. No s-video, no analog pass thru, and no smart antenna input. And a rather limited now/next program guide. But it seems to be about the best you are going to get in a stripped down model at local retailers. All the units at the big box retailers look like stripped down minimalist models. You should be able to walk into those stores and have a choice of a value model or a performance model for $20 more that has ALL the features allowed by law. But you can't get a single box that supports all the legal features, period.
The Tivax STB-T9 (online) and similar units ar notable for having an RS-232 port but this is only used for software upgrades, it won't work with your TiVO or other device to change channels (actually, it will if you have a device you can program). Schematics can be downloaded from their FCC filings (see below). From their shitty website, Tivax doesn't exactly look the kind of company you could rely on to actually provide updates.
The APEX DT250 has svideo, analog pass through, smart antenna, and a 3 day program guide but won't be available until after the first coupons expire.
The DISH network DTVPPal, has analog passthrough, full program guide, and a timer mode for unattended recording but won't be available until the first coupons expire.
Choose your box carefully – if you don't like it, you might have trouble getting a refund; if the reception isn't good, you are stuck. However, I have heard of people getting credit back on their coupons returning a box so the government FAQ may have made it seem worse than it actually was. But even then when I asked a Radio Shack person about returns or exchanges she said you lose the $40. Given that there are no refunds and even if the retailer let you exchange it they often don't have another model, and the “local” stores are chains, there may be little advantage to buying local other than shipping cost. On the other hand, the models that might really be worth ordering online aren't available before many coupons expire. And those that offer more than the bare minimum offer so little more than the bare minimum that they are hardly worth the extra trouble and/or expense to get them.
Microtune, a US maker of tuner modules, has sent a letter to the NTIA alleging that some CECB's not incorporating their tuners failed to meet minimum reception standards; they didn't name the manufacturer, but it was deduced on avsforum that the unit in question was the magnavox/philco/funai model. dtvboxanswers ranks some boxes reception quality good/ok/low. Most of what I have read concerning the Zenith/LG units reception is good. One reviewer writes “the Zenith is based on LG’s ATSC digital tuner chipset, which is known for its superior reception capabilities over most other silicon.” Some Zenith/LG's manufactured before april seem to have an audio problem that shows up on some TV sets. Radioshack has a few extra models online that you can have shipped to the local store but a few online sources seem to indicate that they have poorer reception quality though hdtvexperts used an attenuator and reported not much difference. Dtvboxanswers lists the GE units as having only “OK” reception and some have reported being able to get channels with the Zenith that they couldn't with the Digital Stream. It is possible that which unit performs best depends on which channel and the types of multipath interference. And some models use one of two different tuner modules so performance could vary based on which you get.
There are a number of different types of tuner performance that could affect your results. Weak signal sensitivity, adjacent channel rejection, multipath interference rejection, and receiver desensitization due to strong channels. Thus while one box may work better for someone, your results could be opposite. Use TV Fool or antenna web to see where your signals are coming for and a rough estimate of their absolute and relative strengths. Antennaweb is thought to underpredict reception.
Some people get the same channels after switching boxes, some get more channels, some get fewer, and some might get about the same number but different channels. As an example of how wide the range is, one person went from 26 channels to 9 while another went from 4-1/2 channels to 12 with 11 having better quality than the best analog. You get the digital subchannels as well as the main channels, too. A study of channels before and after can be found at TV Fool .
Note that if you have trees, hills, or buildings between you and the transmitter, try aiming your antenna at the tops of these obstructions rather than horizontal or where you think the tower is (I.e. Tower lights that you can see from just the right angle). The signal diffracts around the edges of the obstruction.
All units are required to have some level of signal quality display. Some will show you more than one metric and/or give you an audio indication. Both enhancements are helpful for antenna aiming. The beep, possibly extended using a cordless phone, is helpful if you have to go outside to adjust your antenna. Also, some show colors (red, yellow, green) though not necessarily in a meaningful way. Red chould mean “I can't decode the signal now without errors”, yellow “I can decode the signal now without erors but my margin of error is less than the statistical variation in signal levels, and green means signal good even with statistical variation in signal. Another interptetation would be Red: can't display a picture at all, yellow can display a picture with deterioration, and green no errors.
Do not compare signal strength meter readings from one box to another; they are generally not calibrated in real world units.
Reportedly, all the CECBs have to meet tougher specs than have been required of any older digital TVs, set top boxes, etc.
An article (puff piece) on silicon tuners.
One of the areas the units differ a lot is the quality of the electronic program guide. Some will only show you the current program on the channel you are watching. Some will show you now/next on all channels. Some will show you a limited number of hours of program guide information on one (current) or all channels. Stations are required to send a minimum of 12 hours of program guide via PSIP and can send up to 16 days. One station engineer reports that he only sends 48 hours and that is the case for many others and most recivers don't have enough memory for 7 days. In addition, gemstar TV guide on screen data for all channels may be sent over one local station (usually PBS or CBS); the Echostar TR-40 unit is supposed to be able to use this info. The PSIP data is only available for the current channel unless the receiver remembers data from other channels you have visited. There is some indication that boxes that try to handle more than now/next exhibit some problems with crashing.
If you have a TV set, DVD recorder, PVR/DVR, or other unit which has puilt in TVGOS guide data that was transmitted via NTSC, it will no longer work after the switchover or after you install your converter box.
I would imagine that channels broadcast now/next (or rather, the
current three hour block) fairly often and program data further out
takes longer and A/69 standard confirms this. Program information is
stored in 3 hour blocks in the Event Information Table (EIT) with up
to 128 EIT blocks (16 days). A/69 says that EIT-0 (current 3 hour
block) has to be sent twice a second, EIT-1 (next 3 hour block) once
every three seconds, and EIT-2 and EIT-3 once a minute. EIT-4 and up
suggested once every minute. Start times for EITSs are 0:00, 3:00,
6:00, 9:00, 12:00, 15:00, 18:00, and 21:00 UTC; in other words, they
don't advance every hour or half hour.
Thus, if I was transmit
EIT blocks every quarter second, I could transmit the minimum
recommend 72 hours of programming information (EIT-0 ... EIT-16),
meeting the recommend and required timing by repeating every 14
seconds like this where a two digit number gives the EIT block
number:
00 01 00 02 | 00 03 00 04 | 00
05 00 06 |
00 01 00 07 | 00 08 00 09 | 00 10 00 11 |
00 01 00
12 | 00 13 00 14 | 00 15 00 16 |
00 01 00 17 | 00 18 00 19 | 00 20
00 21 |
00 01 00 22 | 00 23 00 xx |
If I was
transmitting 16 days, this would take 128 seconds so I would have to
transmit EIT blocks faster to meet the 1 minute suggested repetition
rate. It is recommend that at least 72 hours (24 blocks) be sent.
Stations may only update the EIT blocks once per 24 hours so 1/3 of
the blocks may be stale, thus sending 72 hours may only show you 48
hours in advance. If I extend this cycle at the same data rate, I get
about 8 days (7 usable) sent once a minute.
Memory
requirements: Each block is 970 bytes, call it 1K with overhead. 128K
bytes for 16 days per virtual channel. Thus 50 channels with 4
subchannels each would be 25.6MB which is why many boxes won't store
a full program guide. Since EIT blocks may not slide, to get now/next
information could take 3 seconds. If one block covers 3-6PM and one
covers 6-9PM, then at 5:50PM, you need EIT-0 and EIT-1 to get
now/next information.
It is assumed in A/74 that the receiver
will scan channels each time it is turned off. If you don't
turn your box off, it can't scan for program guide information since
it has no way of knowing if you are actively watching which prevents
it from changing channels. Assuming your box has at least 48 hours
worth of EPG memory, that you turn your box off at least one hour per
day, and stations meet the minimum recommendations, you should have
24-48 hours of EPG information available at any given time. If your
box has less memory, time to retrieve program information for the
current channel would be:
now: 0.5 seconds
next: 3 seconds
next
3 hours: 0.5 to 3 seconds, depending on time of day and hour in
question
next 12 hours: 1 minute
next 16 days (to extent
available): 1 minute
If you have two dozen physical channels, it
will take your box 24 minutes to scan all the channels to get program
guide info when you turn it off. Assuming the box takes 1 second to
acquire a channel and 3 seconds to get EIT-0 and EIT-1 on each
channel, the box could first spend 96 seconds grabbing the next 3-6
hours and 45 seconds scanning for new physical channels and
added/deleted virtual channels on the other physical channels before
it tries to acquire the rest of the program guide info.
If you don't turn the box off each day but channel surf spending at least one minute on each channel, the box should be able to grab the data, if it is smart enough to grab it on the fly.
The CECB Feature list and wiki are a bit vague about the EPG
features (memory, when it is obtained, and how it is presented):
Current: only shows current show on current channel?
24-hour: 24 hour program guide on current channel or all channels?
Now/Next:
on current channel only?
one channel at a time but allows showing different channels without actually channels?
One channel at a time but allows showing different channels by switching channels?
now/next grid for all channels without switching?
8-day: 7-8 days on current channel or all channels?
7-day TVGOS: approximately 7 days on all channels
14 day: 14 days on current channel or all channels?
I will illustrate with a hypothetical test of a Zenith style now/next converter box in a particular location.
The idea would be to unplug the unit (not merely turn off) for a few days (as many as it appears to have data) to deplete the memory so you can see when it gets populated. Note that if box doesn't have flash or a battery backup, unplugging for 10 seconds may suffice.
Then carefully experiment with the unit. If a DVR or VCR is available, set it to record output of box while experimenting. Suppose we have the following channels (zipcode 22903):
16-1, 19-1, 19-2, 27-1, 27-2, 29-1, 29-2, 29-3, 41-1, 41-2, 41-3.
Now, we should really look up on TVfool which physical channels are which since we have one company broadcasting three different networks but it turns out they are using separate frequencies. I will assume a now/next zenith type box that lets you scroll through channels without actually tuning to another channel but may tell you there is no data. I am guessing, here based on the unit doing the best that it can, storing EIT-0 and EIT-1 only for each channel. I.E. it is storing a little more info than it shows. Do not change channels except when part of the experiment to avoid acquiring extra data. Also, an unexpected result at any stage of this test could affect the assumptions in following tests; you need to know enough to adapt.
Set channel to channel 16-1.
Unplug unit to deplete memory
Plug unit back in and immediately turn on
Hope we are still on 16-1
pull up program guide. Scroll through channels without tuning. Should see program listings for 16-1 only. If we have program data, this may be an indication of flash/battery backup (either of which is good but could wear out). Rest assumes we only saw 16-1. Exit program guide.
CH+ to 19-1,
pull up program guide. Scroll through channels without tuning. We expect to see listings for 19-1. We should see 19-2, and 19.3; if not, we have a bug (failure to store other virtual channels on same physical channel. We should also see listings for 16-1, if not we have a bug (failure to remember other physical channels). We will not see listings for 27-*, 29-*, and 41-*. If we do, the unit a second tuner for guide data (not likely), is telepathic, or we screwed up.
Turn unit off for 3 minutes (but keep plugged in), then turn back on and pull up program guide. (Are we still on 19-1? This tells us if we have last channel memory as long as power is applied.)
We should see now/next guide data for all channels. If not, we have a bug (failure to scan channel data when first turned off).
Stay tuned to 19-1, for just over 1 hour (assume programs are less than 1 hour) with the box on so it can't scan.
Pull up program guide and scroll through channels without tuning. We should still have now/next information for all channels. If not, we have a bug (failure to store EIT-0 and EIT-1 for each channel, storing ONLY the now/next shows).
Stay tuned to 19-1 for just over 6 more hours. Note that this test is similar to watching a movie or a couple of consecutive shows on one channel without changing channels. Data will become depleted due to expiration in roughly 3 to 6 hours. We give it 6 in case we started at a best case time.
Pull up and scroll through program guide without tuning. We expect to see no program listings for any channel but 19-1, 19-2, and 19-3. If we see more, we have a feature: storage of EIT-2 and EIT-3 and we should also check to see if it stores more than 2 and 3.
Unplug unit for 10 seconds (more if non-volatile), plug back in, and leave turned off for 5 minutes. When we turn on and look at program guide, we should have now/next data for all channels. If not, we have a bug (failure to scan after power failure).
Note time in both local time and UTC when doing tests at the start of the test and after each long delay. EIT blocks start at hours divisible by 3 in UTC, not local time. Thus the time you do the test dictates how much usable data is in EIT-0 and EIT-1.
These tests require some understanding, not just following a recipe because you have to adapt the tests based on what you learn along the way.
For some, it may be helpful to use UTC and draw a chart on a piece of graph paper with virtual stations, grouped by physical channel, across
the top and time in UTC down the side in 1 hour or half hour blocks.
Group each block of three hours (starting at UTC hours divisable by three) together and write down the EIT number. Draw heavy lines at physical channel boundaries and the 3 hour boundaries. Then, when you tune each station, you can put an X in the blocks for what data the converter appears to be able to access.
A lot of the variation is whether the units support S-video output, smart antenna input, and analog pass through, since these require some extra cost components. Most units are missing these and only one, the Apex DT250 which hasn't shipped yet (June 2008), has all three. TV passthru requires a relay or a notch filter and signal injector and may attenuate signal slightly. S-Video output requires a connector and maybe a driver but the chipsets probably have the signals.
Analog passthru is needed during the transition before the switchover as well as for stations that will not be switching over. Low power, Class A, and translator (repeater) stations, Canadian, and Mexican stations don't have to switch. There is even an attempt to exempt US full power stations near the mexican border since part of their audience isn't eligible for coupons. There are also many devices that may generate a NTSC signal that needs to be passed through. Security systems, VCRs, video games, whole house distribution of DVR or other content.
All video components should have an antenna in and out connection with passthru. They should also have composite video and stereo audio (RCA jacks) input and output with passthru. Likewise for S-video. Other I/Os should also have passthrough. This allows you to daisychain units. VCRs, DVD recorders, and other recording devices, which have to have have these jacks anyway, normally have this capability. TV's which are often the end of the line, often do not. DVD players usually do not (get a DVD recorder instead). Game consoles usually do not.
Having more than one video input is also highly desireable. Having more than one output is sometimes useful as well.
Wikipedia lists the chips used for various functions, where known. The recent generation LG chipsets used in the Insignia/Zenith and many others have a good reputation for handling weak signals and multipath interference.
Some of the CECB boxes use the same remote control codes as cable boxes. From tivocommunity we have a few. This means that TiVo's and possibly some smart VCRs, can control the box using an IR transmitter.
Channel Master CM-7000 – pioneer
Zenith/LG DTT900 – LG directv receiver (TIVO 10075-B)
RCA DTA800B – RCA directv receiver
On analog TV (NTSC) captions were encoded onto line 21 of the vertical blanking interval, part of the black bar that is normally off the edge of the screen, according to the EIA/CEA-608 standard. If you adjust the vertical hold control on a TV (that still has one), you can actually see the captions encoded as light and dark. A digital signal doesn't have a vertical blanking interval. On digital TV (ATSC), EIA-608 analog TV captions and EIA/CEA-708 digital captions are both merged into the digital bitstream. The converter box is required to take the EIA-608 captions and inject them into Line 21 so your VCR can record them and your TV can decode them. Most digital stations are required to transmit captions in both EIA-608 and EIA-708. EIA-708 allows more caption data to be sent and the content author can select more font sizes and colors than a TV (with its legacy decoder) may provide and the user can override those font settings. If you record the video on a VCR, you probably want the EIA-608 captions so you can decide whether or not to display them at viewing time. EIA-708 to EIA-608 caption translation is somewhat limited as 708 supports many features that 608 does not so some information (primarily presentation) is lost. All CECBs are required to pass thru the EIA-608 captions. They may optionally render the EIA-608 captions at the user's request. They may optionally display the 708 captions directly for a better quality display.
On a DVD player, there are two forms and you will see that some movies have one, some have the other, and some have both. One is digital captions (CC) that get encoded as EIA-608 and inserted onto Line 21 and are decoded in the TV. The other is a prerendered graphical overlay (subtitles) that has more flexibility in terms of fonts and positions and gimmicks but has lost its encoding as ASCII/UNICODE text. Since it has lost its abstract text encoding and become pixels, it is problematic to implement such features as text searching, automatic transcription, or driving a brail reader.
An article on captioning with block diagrams of how the encoding is handled at a TV station. wikipedia has more.
Some folks have [URL="http://screenfont.ca/fonts/today/708/"]scathing criticism[/URL] of tiresias, which they consider unsalvageable, and other fonts commonly used. Sure, tiresias doesn't look too bad if you are close to a good quality TV. But captioning places some incredible demands on a font. People with a wide range of visual and hearing impairments, dyslexics, plus non-disabled people and 2nd language people, have to read at high speed, while also paying attention to action, and for long periods of time and from way too far away, against a possibly transparent background neccessary to not obscure the action, a font that could be rendered on a sharp HDTV to a crappy interlaced analog TV with poor focus over an RF modulator connection, could be resampled with jitter on an analog LCD, rescaled on a high resolution display from a low resolution source,prone to halation, or anamorphicly projected. Captions may be further mutilated by VCR recording or DVD recording (with compression artifacts). Caption fonts, including tiresias, are typically derived from Print fonts, intended for non-luminous high resolution use and computer fonts intended for close viewing of a high resolution screen. Tiresias was developed in such a way that it is subject to the high prices ($17,400) of professional font foundaries while the people doing the work weren't getting paid for it (and it shows).
Captions are transcriptions of the dialog and sound effects for deaf users. Subtitles are dialog plus some on screen text for people who speak another language. You can have both and may sometimes need both; what if you are deaf and you speak a different language? Captions may also identify the speaker which is helpful since voice cues are missing and can be helpful for people with face blindness. Secondary audio channels are sometimes available in which an announcer, speaking very fast, describes the action on screen during pauses in the dialog. The majority of caption/subtitle users are not deaf or visually impaired. Most are non-native English speakers. Many other people use captions/subtitles as well.
If you watch 2 hours of TV five days a week, you will read about 4.4 million words a year. That is about the equivalent of about 59 novels. And unlike a book, you can't backup and reread – unless you have a DVR or are watching a DVD.
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Links: Typography and TV captioning ,
An NTSC signal consists of:
Composite Video
525 scan lines, interlaced into two separate fields
Luminence (brightness)
Chroma (color - hue/saturation)
Horizontal Sync, colorburst, and blanking interval. Sync tells the TV set where each new line starts, colorburst provides a reference for color decoding, and the blanking interval provides a reference to measure the sync pulse against and provides time for the electron beam on CRTs to return to the left edge of the screen.
Vertical Sync and blanking interval. Sync tells the TV set where the start of each field (half frame) begins. Blanking interval provides time for the electron beam on CRTs to return to the top edge of the screen. Since a TV can sweep the electron beam back to the top of the screen faster than the time allotted by the blanking interval, there is some room left over to shoehorn in some digital data.
Line 21: Closed captioning, DXS, and V-Chip
Line 12-14 – SMPTE timecodes (for editing)
Line 14-18, 20: teletext (not widely used)
Line 17-18 – test data
Line 11-18,20,22 – TVGOS (TV guide, one station per region)
Audio
Left + Right (Mono)
Left – Right (Stereo)
Secondary Audio Progam 1
Secondary Audio Program 2
Pilot – signals that stereo is being sent
All four are transmitted on the RF signal. L+R and L-R are decoded into left and right and brought out to RCA jacks, on devices that have A/V outputs. SAP is lost unless the originating devices is told to decode SAP, in which case the left and right signals and the other SAP channel is lost
This is a rough approximation of a digital TV transmission protocol hierarchy. Since ATSC doesn't seem to provide a good overview document, I have had to make some guesses based on skimming various standards documents. Virtual channels may not be broken down into separate substreams but instead all video and audio streams might be immediate children of the main transport stream with only the control tables to tell a receiver which streams correspond. Thus, there are a number of places where the logical hierarchy may be flattened in the protocol hierarchy or things may be otherwise positioned incorrectly. ATSC looks suspiciously like it is not well layered.
One physical channel (2-69), 6Mhz bandwidth. 8VSB modulated digital signal, up to 19.39 megabits/second. One channel could be carried on a baseband ATSC signal (rough equivalent to composite video) but normally, it occupies a single channel of the TV broadcast spectrum. It may also be sent (modified?) over IEEE-1394 (Firewire).
Transport Stream
Virtual Channel 1
Video. MPEG2 (elemental stream)
Compressed video data
DTVCC (captions) transport channel
EIA-608 (analog TV CC)
EIA-708 DVTCC Caption Channel
Caption service 1
Caption service 2
...
Audio. (elemental stream) Multiple audio streams. AC3 encoded. 1 to 5.1 channels. Service types: complete main, music and effects, visually impaired, hearing impaired, dialog, commentary, emergency, voice-over. Some streams may need to be mixed with the music and effects stream. For example, you can have multiple languages of stereo dialog that are mixed with the 5.1 channel music and effects.
Virtual Channel 2, 3, ...
Program and System Information Protocol (PSIP)
System Time Table (STT)
Master Guide Table (MGT)
Terrestrial Virtual Channel Table (TVCT)
Event Information Tables (EIT) (Program listings)
EIT-0 - Current 3 three hour block
EIT-1 - Next 3 hour block
EIT-2
EIT-3
EIT-4 to EIT-127
Also contains some data about captions.
Rating Region Table (RRT)
Extended Text Table (ETT)
Directed channel change Table (DCCT)
Directed channel change selection code table (DCCSCT)
Program Association Table (PAT)
Conditional Access Table (CAT)
Program Map Table (PMT). Also contains some information about captions.
Network Information Table (NIT)
Transport Stream Description table (TSDT)
MPEG Private Section
A/90 Data services – May be TV related or have little to do with TV.
ATSC Data Download (MPEG2 private section)
Converter box/TV firmware updates??
Other download services
Addressable sections (MPEG2 private section)
TCP/IP
ATSC Data Piping
TV Guide On Screen (TVGOS) may fit in here carrying enhanced program listings for all local channels on one local station (licensed data). Is TVGOS sent over a pipe, a stream, or as a data download? Piping would be most analogous to PSIP.
ATSC Data Streaming (MPEG2 elemental stream)
Datacasting services may include news, weather, traffic, stock market, gaming, shopping, or educational material. Some are interactive and may require an alternate channel to send data back.
Competing standards to ATSC for digital television include DVB-T (Used in Europe ), DVB-S (used by Dish Network, globecast, and BellExpressVu) satellite broadcasts), DVB-C (cable) and QAM64/QAM256 used by cable systems, DirecTV's non-standard proprietary system, and others. QAM cable systems in the US substitute QAM for 8VSB but still transmit ATSC formatted data on top of that, though for many channels it is encrypted.
This is a rough guess of the cost of added hardware features. It is based loosely on qty 1 prices for components at a high priced full service US distributor, though I didn't look up every part. Allowances were made for support components. It includes Actual cost of adding a feature exceeds component cost; I.E. There is some markup for board space used, solder, assembly costs, and proportional increase in profit. However, in mass production quantities, component cost would be less than half the qty 1 cost.
Analog RF passthru $2
A/V (RCA) passthru (composite video, left/right audio). $5
Extra front panel buttons: $0.50 each
Extra remote control buttons: $0.10 each
Smart Antenna connector: $4
Enough memory for full 16 day program guide: $4
Component/RGB outputs $4 (not allowed by coupon program)
Duplicate A/V outputs $4
Over the air firmware update: $2 (extra memory needed to double buffer firmware in case download is incomplete or aborted. Can be avoided by using program guide RAM to download and only flashing the software when it is complete at the risk of bricking the unit if a power failure occurs at the wrong moment)
RS-232 software update: $2
Real-time clock for auto wakeup (for example for unattended VCR recording): $4 or less. Not needed to provide this functionality if you disable autopower off.
Universal remote. $3
TV power control, switched.
TV power control, via remote (basically a very limited universal remote).
These are the features that add nothing to the marginal hardware cost of the unit. Indeed, they add nothing to the marginal cost at all since the cost is the same whether you sell 1 or a million units and they add only a small amount to the amortized development costs. These are basically software. If you spend $25,000 extra on software and sell 100,000 units (if you expect to sell fewer, you probably wouldn't bother competing for a mass market commodity item like this) that costs $0.25 per unit. If you sell a million units, it is only $0.025 per unit. It is possible to make the program larger than the amount of code memory supported by the hardware, though this is less likely if you avoid wasteful programming practices. In that case, upgrading the memory chip could add a couple bucks to the cost of the unit.
Pretty much everything legal under the coupon program not listed under extra cost features falls into this category.
You might think channel selection would be a simple issue but guess again. A TV station in my area, “Channel 29”, for example, broadcasts an analog signal on channel 29 and a digital signal carrying logical channels 29.1, 29.2, and 29.3 on physical channel 32. After the transition, it might stay on 32 or move to 29 or in some rare cases move to a different frequency entirely to minimize interference. As part of the setup process, a CECB will scan all channels to find those that are in use and have a strong enough signal and will detect what logical channel numbers are in use. However, a user may want a distant station that carries content not duplicated locally even if the signal is not strong enough to be received clearly at all times. And not all channels may be broadcasting at the time you run the autoscan and your antenna might not be pointed in the right direction to pick up a particular channel at that time. A box may also reject signals it considers too weak to reliably receive consistently. All boxes should thus let you manually add channels that were not picked up by the autoscan; some do not. All boxes should also have the ability to perform additional autoscans without erasing the old channels from the list; some do not. All boxes should also let you manually enter a channel that isn't on the list of channels detected by autoscan or on the smaller list of channels the user has selected. In order to protect a TV stations branding and avoid confusing viewers, the logical digital channels are still numbered 29.x rather than 32.x. Unfortunately, this creates more confusion when a user must manually enter a channel that wasn't picked up on the autoscan. If you want to tune to this station and it wasn't autoscanned, what do you enter? “29”, 29.1”, or 32? Since it didn't read the metadata for this channel during autoscan, entering 29 or 29.1 isn't going to work since the box has no idea what frequency is being used. Some boxes will let you enter “32” and if that doesn't correspond to a known logical channel it will instead try tuning to physical channel 32. Other boxes may not be that smart. Things would get even more confusing, though, in an area where there was also a logical channel 32, in which case that style of user interace would not let you tune to physical channel 32. This isn't likely pre-transition but could happen post-transition if a new channel takes over a vacated channel; this is something that the new channel or the FCC may try to avoid but in some cases it might be necessary and reportedly there will be cases such as this.
Many units have channel up/down buttons on the front panel, as well as the remote, but some do not. These will allow limited use of the device when you have misplaced the remote, the remote is broken or has dead batteries, or when you are located next to the equipment and not in your normal viewing location. Most boxes that have power and channel buttons don't have menu and select buttons, and even some that did may not have menu options corresponding to all of the functions on the remote. Thus, all or almost all, devices will be only partially functional at best with a dead remote. If there is even a single box on the market that handles this properly, I am not aware of it.
Cable/satellite users don't need converter boxes (at least until 2012), with several notable exceptions:
You expect to drop cable service before you upgrade your TVs to digital
Emergency use. Every household should have at least one TV capable of off the air reception in case of emergency. Hurricane Katrina, for example, knocked out cable systems for weeks, just when it was needed the most. Battery operation is desirable as power may also be lost. Integrating the converter (so you don't have to rewire your system in an emergency (or to check that it is still functional), which many people can't do by themselves) with your system may require analog passthru, external switchboxes, etc.
Satellite users who don't get local channels via satellite. Integrating a CECB with your system may require analog passthru.
It should also be noted that scanners, emergency radios, ham radios, etc. that were previously able to pick up the audio portion of TV broadcasts will no longer be able to do so.
The APEX DT250 has all three of the scarce I/O features (S-video, analog pass through, and smart antenna), 3 day program guide, a 23 page manual, and a cheap price. On the downside, APEX is not known for high quality construction (though that is hardly unusual these days). APEX does offer good bang for the buck, at least in the short term. I am still a bit peeved that my APEX TV/DVD player developed two electrical problems (loss of vertical scan and refusal to power on) and one mechanical one (tray load) in 4 years and became too much trouble to fix even though I bought the service manual.
I am also not sure from the manual that the 3 day program guide is presented in more than one channel at a time. And the box appears to be missing a manual channel add or add only autoscan.
The TR-40 has analog passthrough, a “full” program guide, a US built microtune tuner module, and it is apparently the only one with a recording timer. And I think it was the first one announced with passthru. Unfortunately, there isn't a lot of info on it, there are no front panel buttons, it uses an external power supply, it has an oddly shaped enclosure, and it hits the market too late for people who registered in 1Q2008. A recoding timer is clunky, because you have to program two devices to setup a recording, but it is better than the alternative. Reportedly uses TV Guides EPG rather than just what you get via PSIP but apparently that isn't true. Other aspects of the DTVpal seem not to be living up to expectations, now that the unit is out. Like the timer not working properly.
This was the first unit I actually saw in the store. Was immediately put off by the lack of channel change buttons.
Hdtvexpert referred to these units as “troublesome” and <a href=”http://www.avsforum.com/avs-vb/showthread.php?t=986114”>avsforum</a> starts with a good review of the receive sensitivity but one poster drove 35 miles to walmart to get one, got one that was DOA, took it back and got another DOA. Other posts about tuner sensitivity weren't as charitable. The magnavox unit is made by Funai; I have one of their DVD recorders and it has worked fairly well. The electronic program guide only shows one show at a time, not a grid. User manual: http://www.funai-corp.com/6pdf/om/TB100MW9.pdf Someone suggested the philco tb100hh9 looks the same as the magnavox, except a different color. Some reported that the unit was running at 110F but drilling some ventilation holes dropped it to 87F. You can't manually add channels without rerunning a channel scan. In april someone said all the Magnavoxes had been pulled from walmart shelves; and indeed they were missing at my local store but they turned up at Sam's club. Another report said that where there are loLts of channels, the tuner fails. Signal meter is not available until after the station decodes – makes it hard to adjust your antenna. The lack of manual channel add is a big problem. If you run your scan when a station is off the air, subject to interference, or you antenna rotor is pointed the wrong way, you have a problem. On avsforum, “The Magnavox is not held in much favor.”
The MW9 does not have analog passthru. The HH9 and MG9 do but it is very cumbersome to use. You go into the setup menu and change from CH3 or CH4 to RF THROUGH to enable and to disable you hold down the setup button on remote for 3 seconds. If your TV has composite A/V inputs, one workaround is to leave the RF in passthru mode and switch the TV from Antenna to AV input; of course that is about the same as using an external splitter on a box that has no passthru (though you lose a little bit of signal that way. Passthru only works when unit is on. Rumor has it that analog RF passthru can be enabled by adding a jumper.
The remote control is unpopular. Small buttons, poor layout, can't
be programmed to even control TV power.
This is the DTT900 upgraded with analog passthru by substituting a TDVG-H151F tuner module. Also fixes some other DTT901 bugs.
Like other boxes available in big box retailers, these are bare bones units. Except for an audio problem (see below), these units tend to have a fairly good implementation of the features they do provide..
While these boxes have the same hardware, there may be differences in the firmware. Insignia is LG's premium brand and Zenith their low end brand. One report said the insignia has a better signal strength meter but another report, substantiated with pictures showed they were the same. Perhaps this was missing from early firmware. Lets you do a fresh channel scan, scan for new channels without erasing old, and manually add channels. If the audio volume is weak (a common issue with CECBs), it helps, strangely, to tell the box using the menus that you are using the RF modulator, not the A/V out.
Units manufactured before 2008-04 may have an audio problem when decoding dolby 5.1 broadcasts that shows up on some TVs and causes a chirping in the left channel. Other boxes using the LG chips seem to have the same problem. Someone on avsforum wrote: “I spoke to Zenith/LG representatives at NAB 2008 and the culprit is an EQ setting in the audio processor. This has been upgraded recently (as has the processing chip). Apparently the problem occurs with a down mix of a Dolby Digital 5.1 surround audio track to stereo, and is not as common when watching programs with native stereo soundtracks.”
FCC documents with test reports and internal photos here
As you can see from one of the video reviews, the now/next program guide only shows two programs on one channel at a time. You can scroll through channels (but not time) using the arrow keys, but it may tell you it has no program guide info and you have to tune to that channel to get it. As you are scolling channels, you can still hear your program and see parts off it.
This one has been showing up on ebay for $40 + $15 postage, no coupons. It is rumored to be a mustek box. There is also a RJ1000ATSC which apparently is not coupon eligible but has QAM, coax digital audio, and RGB/component as well as passthru and s-video (but no smart antenna) and firmware update. not available as of 2008-06. This box was registered with the FCC by Shenzhen MTC and is also known as the Alpha Digital AT2016, AMTC AT2016, and appears to be the same as the Tivax STB-T9. Also may be same as Mustek MAT-K50. FCC ID UVD20071228001 (includes schematic, internal and external pictures). This box has an RS-232 connector for software upgrades, described in one of the manuals as for factory use only. The Tuner/RF modulator used in these models shows an optional analog pass through on the block diagram, but that doesn't appear to be the version used on these boxes. The Shenzhen MTC FCC registration shows a front panel with the RJTECH part number on it and the back panel picture shows the AT-2016 part number. Note that Shenzhen is a city in China, and appears in many company names. The Tivax and Mustek were judged to be likely relabeled units since the position of the front panel controls, the back panel, and the remote control matched. The front panel bezel looks different across different models. MTC represented to the FCC that AMTC AT-2016, Mustek MAT-K50 DTA1010, RJ-900ATSC, RJ-1000ATSC, STB-T8, STB-T9, and STB-T10 are “identical in the hardware aspect”. However, that is not likely true for the RJ-1000ATSC since it has a number of connectors for which there are no positions on the PCB. There may be cosmetic and firmware differences. On the Tivax, people have been able to get a monitor prompt on the RS-232 port. One of the commands is “satune” which probably lets you set the channel and zir which simulates pressing buttons on the remote control. The memorex MVCB100 may be a similar unit but with passthru. The Tivax has heat sink, ventilation holes, and metal case. The tivax is reported to have a remote control with most functions directly accessible from dedicated remote buttons, pretty good reception, and retains channel setting after a power loss. One user reported as much as 11-1/2 hours of EPG so it is probably remembering EIT-0 through EIT3; it looks like a now/next interface but you can scroll using the arrow keys. It is reported to have some zoom and overscan issues and not great multipath rejection. No easyadd or manual channel add, though if you enter the physical channel number it will pick up the logical channels there and you can then see them in the add/remove channels list.). Has a dash button for subchannel entry. Caption fonts are poor and don't survive interlacing well.
This one is confusing because there are three different models with different letter suffixes but the letter suffixes are often omitted. The A model uses a Zoran chipset and the B and B1 models use a broadcom chipset. The RCA has a [Hidden Menu] but it doesn't apparently do much.
This information comes from the avsforum thread where Malouff posted the screendumps of EPG. This is probably indication that the boxes are running the same basic firmware (and probably the same processor chip), but doesn't necessarily imply hardware equivalence:
DTVPal
RCA DTA800B, RCA DTA800B1 (DTA800A uses different chipset)
Channel Master CM-7000, Suspected: MAG CCB7707?, AVION ATB 7707?
GE/Jasco 22730, GE/Jasco 22729 (enhanced), Goodmind DTA1000, Goodmind DTA9000, Suspected: Goodmind DTA980?, Zentech DF2000?
Digital Stream DTX9900, Digital Stream DSP7500T, Digital StreamDSP7700T, Suspected: Digital Stream DTX9950 (adds passthru), Digital Stream DSP6500R, Digital Stream D2A1D20, Digital Stream D2A1D10, Digital Stream DX8700
Magnavox TB100MW9, Magnavox TB-100MG9 (adds passthru?), Philco TB100HH9, Suspect: Philco TB150HH9
Tivax STB-T9, MicroGEM MG200, Apex DT250, AccessHD 1010D, AccessHD 1010U, AccessHD 1020U, Suspected: AMTC AT-2016. The Tivex STB-T9, AMTC AT-2016, Alpha Digital AT-2016, RJTECH RJ-900ATSC are all the same hardware. MicroGEM and Apex are definitely different hardware.
Zenith DTT900, Insignia NS-DXA1. Zenith DTT901 and Insignia NS-DXA1-APT might be the same but with passthru.
Artec T3APro, Artec T3A, Suspected: Kinkbox K8B8, Kingbox K8V1
CASTi CAX-01, Daytek CAX-01
Winegard RC-DT09, Venture STB7766G
Sansonic FT300A, Sansonic FT300RT, Lasonic LTA-260, Gridlink LT-200, Lasonic LTR-260, Gridlink GLT-300
If you have a fast enough computer, you can purchase a digital tuner for the computer for around the price of a converter box (without coupon) and get EDTV or HDTV resolution display on your computer, video recording, and automatic channel selection. There are also devices that let you use your computer monitor as a TV (whether or not the computer is powered up or connected) but not record; so far, these seem to be analog TV only. The latter devices are also usually crippled by not having composite or better inputs.
These standalone tuners are intended for use with HDTV monitors. Samsung DTV-H260F, Samsung SIR-T150, Sylvania 6900DTE, Samsung SIR-T451, Humax HFA100, etc. Note that while they may offer much better connectivity, older units using old chips may not pick up weak stations as well as the CECBs. Some more are listed on avsforum .
Some DirecTV HD satellite tuners are known to work as over-the-air digital tuners without subscribing to satellite service. P
If your analog TV is nearing the end of its useful life for reasons that have little to do with broadcast formats but you aren't ready to shell out for HDTV, then one of the low end digital TVs might be a candidate.
If you were already leaning towards getting cable or satellite, then there may not be much point in getting converter boxes.
Some video recorders are shipping with ATSC tuners. If you don't need to record and watch TV simultaneously, you may be able to use these to convert your signal. Some of these are already cheaper than some standalone HDTV tuners. Magnavox makes an H2080MW8 80GB hard drive/DVD recorder with digital tuner that sells for $200 at walmart. Bear in mind that they may record only at SD resolution and for that matter only convert SD resolution but may have component and HDMI outputs. If you have limited space for A/V components near your TV, a DVD-R/VHS combo with ATSC tuner might do the trick.
These are listed in approximately in order from lowest quality to highest.
RF (antenna)
composite video
S-video
Component video (YPbPr)
RGB, SCART (European TV's composite or RGB video + audio on one connector), or VGA
Firewire (limited bandwidth)
HD-SDI (used on professinal equipment only)
HDMI
DVI
Displayport
Coupon eligible boxes limit you to the bottom two or three rungs of the ladder. DVD quality pictures are degraded by anything less than component video.
8VSB is the modulation scheme used in US digital over the air terrestrial TV and is required to be supported. QAM is used for unencrypted cable, such as basic digital cable so if you have or switch to basic digital cable you can't use it without a set top box from the cable company. Most CECB boxes probably use chips that support QAM but few if any will let you use it. It isn't clear that it is legal to support it. Apparently it isn't. The Microprose MPI-500 might be an exception since it is rumored that it mentioned QAM in the spec sheet, though I don't see that any more. Until a station stops broadcasting an analog signal, must carry rules don't require the digital version on cable to be carried or unencrypted so some some of the more disreputable cable companies, such as Comcast, are reported to encrypt those channels. None of the devices, as far as I know, support NTSC tuning. Sound like a dumb think to include in an ATSC to NTSC device? Well, a lot of the ATSC tuner chips have NTSC capability, you lose less signal than with passthru, and things operate a lot smoother if you have to tune both NTSC and ATSC signals and there will still be some low power analog stations around after the switchover. Non-coupon versions of the boxes may emerge later that include the trivial amount of software needed to enable QAM and NTSC tuning.
DTV converters are complicated devices. Below is a representative diagram. By the time the converter is done with its job, the signal has been processed in many ways. Using the composite outputs on the converter instead of the RF output, avoids a few processing stages in the converter and the next piece of equipment down the line. The two digital stages that affect the quality are the Resolution_Down_Converter and the Frame_Rate_Converter.
This diagram automatically generated from a description of the interrelationships using graphviz.

Note: evil software has flattened this outline. Plus signs inserted on list elements that should be indented.
Reception? Link to TV fool report (analog+digital) for your location (gives approximate signal strengths and congestion)?
Picture Quality on standard definition analog TV? S-Video, composite, or RF used? Closeup picture of portion of screen.
Picture Quality on HDTV ready TV? Obviously it will not be high definition. This depends on the TV's upscaler as well as the box itself, and is thus meaningful primarily when compared to other boxes tested on the same system. Horizontal blocky-ness? Vertical blocky-ness? Horizontal blockyness may be reduced if the CECB has a low pass filter on the output.
Left Channel Audio bug (LG chip based units) when listening to Dolby 5.1 broadcast using RCA plugs (not RF)? Absence of symptoms doesn't mean absence of problem as the problem can't be heard on some programs and on some systems.
S-Video and composite in/out?
+Does it have S-video output?
+Does it have S-video input?
+Can you select passthru from S-video input to S-video output for daisy chaining or external device input? Can you treat the input as an A/V input or channel (in the CH+ loop) just as you would on a TV? (For example to select a DVD player). Is it coupled with the RCA audio inputs when you do this?
Does it have a composite video input and right/left audio input jacks?
Do S-video In/out share audio jacks with composite input?
+ can you select passthru from composite video input and corresponding audio jacks?
+Does it convert from composite in to S-video out? S-video in to composite out?
+Is selection between composite input and S-video input manual or auto?
+When you have selected composite or s-video input or passthru, does it pass thru to the RF modulator.
Smart Antenna connection?
+6pin or modulated over coax?
Does user interface let you manually enter the 14bit pattern to be sent for each channel? Or a 7 bit pattern plus channel number?
Does user interface let you do a sweep from 0-127 of all possible codes for best signal? Does it let you change the speed of the scan?
Analog RF Pass Thru
+Has pass thru
+How do you operate it? Turn box off? Menu? Remote key?
+Does passthru work only when box is on?
+Does passthru work only when box is off?
+Is there a signal loss to the internal circuitry due to passthru?
+Is there a signal loss to the next box due to passthru?.,
RF modulator
+Stereo audio (vs. mono) signal sent over RF modulator (not likely)?
+CH3/CH4 switchable (or frequency agile)? External slide switch, remote button, or menu item?
Electronic Program Guide. To understand some of these questions, you need to read the EPG section of this page.
+Does the box show: current program only, now/next one channel at a time, now/next grid (all channels), or a multihour/multichannel grid.
+How many days/hours of PSIP information does the box appear to store? Take into consideration that TV stations may not transmit a full 16 days, so we can just get a minimum bound based on the highest number across all channels. Limits on how far you can scroll might be an indication.
+Does it store for all channels or just the current channel? Some boxes might be able to give, for example, 12 hours of information but only on the current channel and forget that data when you tune to a new channel.
+Is there evidence of non-volatile memory (flash/battery backed) for program guide information?
+Does it appear to acquire PSIP information for all channels when it is turned off for an hour?
+Does it appear to acquire PSIP information for all channels after having been unplugged and then left turned off for an hour (power failure recovery).
+Does it appear to acquire new PSIP information when you channel surf and are not using the program guide.
+Does it appear to acquire full available PSIP information while you are channel surfing , if you spend at least 1 minute per channel? If you spend significantly less than 1 minute per channel does it appear to be populating data if you scroll 16 days into the future?
+If you tune through a channel that sends the full 16 days in say 6 seconds, you might get the next 3-6 hours of programming plus 30 hours at some random time in the future.
+Does it appear to acquire PSIP information when autoscanning for new channels?
+What is the maximum amount of PSIP data sent by any station in the area where your are tested, if you have an indication of this from other equipment of from the station itself
+Does the box retain stored program guide information if unplugged for 10 seconds?
+Can you scroll through the program guide channels without the box tuning to another channel? I.E. can you peek at the program guide and still listen to your current program? Does the box interrupt your program and scan through one or more other channels to acquire data when you load the guide every time, only when it needs info it doesn't have, or never.
+If the box requires tuning to another channel momentarily to get the information, and does so with your permission, does it return you to your original channel?
+Does the box appear to store EIT-0 for all channels you have visited, without using program guide.
+Likewise for EIT-1
+Likewise for EIT-2
+Likewise for EIT-3
+Likewise for EIT-4+, how far out?
+How much detail does it give on each progam (current, next, 1-3 hours out, 3-6 hours out, and further out? I.E. is it throwing out data for programs that don't come on for a while to save space?
+Does the box crash occassionally? Any indication may be EPG related?
+Are there performance problems in the general use of the box that appear related to program guide information? If the box has a way to turn off the program guide, this can help compare.
+Will the box show you as much data as it appears to remember or is the user interface more limited in what it will display? Example: retaining 3-6 hours (EIT-0/EIT-1) but only showing now/next.
+Does the box have a function you can invoke to initiate population of program data for all channels? I.E. push a button and it scans all the channels while you take a potty break. Does it offer quick (1 minute/EIT0/EIT1, 3-6 hours data), medium (3 minutes EIT0 ... EOT3, 9-12 hours data), and full modes (1 hour, 16 days data or max supported)?
+If the box is left off for an extended period of time (days), does it turn itself on periodically to collect program guide information so it will be ready when you do use it?
+Can you select a program on the grid and view program details without changing the channel?
+Does it have a sleep timer that will cause it to go into standby? Some people leave the TV on all day and when they go to bed, thus the box never has a chance to load program data.
+Do you have knowledge of how many hours/days data the local stations transmits? When they update the info? You might have some or all of this based on using a digital TV with full program guide, by calling the station, or because you work there.
+Any quirks? Notable good/bad features?
+Summary question: Does the box opportunistically pick up as much information as it can, subject to a limit of not storing data too far into the future (but at least 3-6 hours), and retain that information? How many hours/days by how many channels (one/all)?
Closed captioning. Most questions stolen from AVS Forum and answers for various boxes can be found there.
+Which digital closed captioning features are available, including enhanced ones such as changing the alignment of the captions and adding an edge to the text to make it thicker and bolder, and the number of colors available.
+Whether or not a button is available on the remote control to operate closed captions directly
+The choices in the menu activated by the CC button and how usable the menu is
I+f analog captions can be decoded by the converter box, the ease of reading the font provided for those analog captions
+The ease of reading the eight different fonts available for digital captions, particularly the default font
+The availability of a "caption preview" of some kind when changes are made in the settings for the digital captions, and how well this predicts the largest font style.
+How large the digital captions are actually capable of becoming: do the longest lines of the largest captions fill the entire width of the screen, and if not, please describe what proportion of the screen is filled by the largest captions.
+How usable the optional translucent background is in providing sufficient contrast to the characters used in the captioning (if it is too transparent, it will be difficult to read the captions)
+Whether there are any bugs associated with captioning, such as a failure to detect analog captions automatically if there are no digital captions, jerky movements of captions, cut-off captions, unexpected changes in the background, etc.
+Whether the remote control has an SAP or audio button to switch to a second audio channel (for descriptive video services), a raised dot on the 5 button, raised dots on the Power button or other buttons (useful for low vision or blind users), or other accessibility issues.
+How well the user manual explains the different digital closed caption settings; please indicate whether it advises choosing Service 1 or explains how to choose it. If you have found the user manual online, please provide the URL if it is not already provided in the first posting.
+Whether the CECB has crashed or otherwise malfunctioned, and what the circumstances were; this question is best answered after extensive use of digital closed captioning with different channels. Please indicate how many hours or days you've been testing the CECB with digital closed captioning turned on.
+Can you reposition the captions? In particular, can you shift captions on 16:9 content down into the black bar area?
+Does the box have voice menus? I.E. Can a blind person operate the menus (once voice menus have been activated)? Does initial setup ask user (with voice on) whether to turn them on or off?
+Is the box color blind accessable? Can you read the menus, dialogs, and on screen displays if you can't distinguish red from green (most common form of color blindness)? If you use a black and white TV? Are user interface colors configurable? Can you select predefined color pallets for color, black and white, and color blind?
+Does the box have a (configurable) option to temporarily enable closed captioning, with a specified default captioning channel, when you hit the mute button?
+Is the remote marked in braile or other tactile indications? Is a braile card describing the remote available?
+Braile Reader: Does the box have the ability to output closed caption data to a RS-232 port (or a USB serial class device) for interfacing to a braile reader? User interface text? Does it have the ability to output user interface text via a EIA-607 closed caption channel for use with a external analog TV closed caption decoder interface to a braile reader?
VCR timer
+Does it have a VCR timer?
+How many programs?
+Remembers channel number after powered off? After power failure? (Important for video recording)?
+Can it activate a remote recorder (I.e. Does it have an IR blaster output?)
Tuning:
+Autoscan from scratch?
+How long does it take?
+Does it populate program guide info while doing it?
+Easyadd (autoscan but don't erase old channels)?
+Manually add a channel
+Can you manually delete a channel? How about a subchannel?
+Can you switch between full (all detected) and favorite channel mode for CH+/CH-? Can you select a mode where you can tune all physical channels (and embedded subchannels) with the CH+/CH-?
+Manually tune to a logical channel? What is the format? If you type “21” do you go to channel 21 or 2.1?
+Manually tune to a physical channel that hasn't been added?
+How long does it take to change channels? If you hit the CH+ or CH- buttons faster than that, does it advance by the appropriate number of channels without pausing for each?
Front Panel
+Power button?
+CH+/CH- buttons
+Ability to control all functions of the box without the remote? (Menu button and all remote control functions available by menu).
Remote control
+How usable is the remote control? What controls are on it?
+Remote controls are required to reuse existing codes. Which brand of cable box does it emulate?
+Ability to use more than one identical box without the remote controls conflicting (unit codes)? How many? Can one remote be used to control multiple boxes (I.e. Quickly change unit code)?
+Can the remote be programmed to control TV power? TV volume? Other TV functions?
+Can the box adjust, by pressing buttons on the remote, the volume level sent to the RCA stereo audio outputs and RF modulator?
On Screen Display?
+What different levels of on screen display are there? What is displayed on each? Does OSD display temporarily when you change channels, etc?
+Is on screen display positioned appropriately so that it does not intrude into the area used by letterboxed 16:9 content on a 4:3 screen (I.E. Stays in black bar area)? How about for 4:3 content on 16:9 screen?
+If the box has multiple video outputs (RCA or RF modulator), can one be programmed to not display on screen display overlay (for video recording)?
Power
+12VDC input? Other DC input? What voltage?
+110VAC input?
++Yes/No
++Internal power supply, power supply with cord coming out of both ends, or wall wart?
++If wall wart, is it power strip compatible (doesn't block other plugs)?
++If wall wart, is it included?
++What is the power rating?
++If Internal power supply, is cord detachable and if so what type of connector?
++Grounded plug?
+Battery operation (besides DC input)? Internal batteries? Rechargable? Charger for external batteries? What type?
+Energy star compliant?
+Rated power in operate and standby modes?
+Actual power measurement in those modes?
+Is power restored after a power failure (important if using a video recorder)?
Aspect ratio? Tested on 16:9 or 4:3 TV? What configuration options are there? Anamorphic issues? Does it properly switch modes for 16:9 vs 4:3 output or do you have to do that manually? How much trouble is manual switching? Button? Menu? How many buttons did you have to push?
Overscan/Underscan configurable?
Cropping? Some boxes cut off part of the top and bottom of the picture above and beyond overscan issues.
Signal Strength indicator:
+Signal strength meter? Bargraph? Numeric readout? Both? Measured in actual engineering units (dBm)?
+Signal quality meter?
+Audible feedback (useful for aiming antenna without being able to see screen)? Can turn off and on?
+Are bar graphs color coded (Red, Yellow, Green)? Does the color coding actually mean something?
Technical documentation
+FCC ID of box? Link to FCC filings?
+Are schematics available for service, modification, and evaluation? Free? URL? Service manual or technical manual?
+Remote control protocol documentation?
+List of major chips and tuner module part number
+All model numbers outside the box. For example, a box might have a public model number XY-200 and another internal one that looks like E123456.
+All assembly numbers inside the box. I.E. Numbers on each board that have to do with the board itself rather than parts on the board.
Manual URL?
Product page URL?
Interior pictures URL?
Electronic Program Guide/Screenshots URL
Special effects:
+Freeze Frame?
Reliability
+Did the box exhibit any crashing, slugishness, corrupted screens (other than normal artifacts of a poor signal), etc?
+Operating temperature of main chip in celsius degrees above ambient ambient after being on for a couple hours in operating mode?
+Temperature of air inside the box after being on (not in standby) for a couple hours, degrees above ambient?
+Heat sink on main chip?
+Plastic or metal box?
+Cooling holes in box?
+Lead free solder? (More likely to fail due to thermal stress, tin whiskers, etc). Presence of a BGA chip would tend to indicate lead free as would solder joints which are less shiny than lead solder.
+Software update? Over the air? Via RS-232? Via USB?
+JTAG: Is there a clearly labeled (TDI/TDO/TCK/TMS) JTAG connector or pads on the board?
+Warranty?
Menu Tree. Reproduce menus in tree (outline) form.
What is in the box?
Identical/Similar boxes?
How does it compare to other boxes you have tested?
These diagrams are intended to help you think about your cabling requirements before purchasing a CECB. If you have already used up all your inputs, a CECB will make things worse by having line outputs but no line inputs.
In these diagrams “RF” connections go from “Antenna Out” on the first device to “Antenna in” on the second device. “Composite”, “Left”, and “Right” connections go from “Line Out” on the first device to “Line In” or “Line 1 In” on the second device. When looking at these diagrams, think about which devices must be powered up to use various operating modes. Usually, a relay will pass through the “RF” signals when powered down but a device must be powered up, and the device set appropriately, to pass through the “Composite”, “Left”, and “Right” connections.
Below is a simple hookup diagram for a TV that only has an antenna input.
Below is a hookup diagram for a TV that has an antenna input and composite input.
Below is a hookup diagram for a DTV converter that lacks analog pass through.
Below is a hookup diagram for a DTV converter and DVD player. Requires that the TV have RF and Composite inputs. Digital TV quality is reduced by only using the RF connection; if your TV has two sets of composite inputs, you can use those.
Below is a hookup of a VCR and DVD player to a TV with RF and composite inputs. Digital TV is degraded by using RF connection (use second composite line input if you have it).. Cannot dub from DVD to VCR. Simultaneous TV watching and recording of a separate program is not possible. Asumes TV and VCR have a single composite Line input each.
Below is a hookup diagram with a DVD player and VCR, set up for dubbing (though copy protected tapes can't be copied). Assumes TV has one set of composite line inputs and VCR has two.
Below is a hookup of a VCR and DVD player.
Below is a hookup diagram with a VCR and DVD recorder. It assumes that you will be dubbing from VCR to DVD more often than the reverse, though the RF cables are connected backwards relative to the composite cables so you can dub from DVD to VCR at reduced quality. Copy protection may limit duplication of commercial videos. Simultaneous watching and recording of separate programs is not possible since there is only one DTV Converter.
Below is a configuration that allows simultaneously watching and recording two separate programs. It allows dubbing from VCR to DVD, with a video stabilizer to clean up signals from deteriorating tapes. Dubbing from DVD to VHS is possible at reduced quality via tha backwards RF connection; copy protection may interfere. Signal quality while watching live DTV is degraded some by using an RF instead of a composite connection; if your TV has a second set of line inputs, use it.
Things are fairly complicated, and I still haven't thrown in a TiVo, game console, IPTV or media player appliance, or a satellite receiver with local channels not available via satellite and thus requiring over the air DTV reception via an antenna.
Here is an example of how a professional might hook up equipment using a matrix switch that allows any input to be connected to any output, using only Composite connections. "Composite/Left/Right" cables have been abreviated "C/L/R". Of course, they might well connect up Component signals or HDMI digital signals as well. They wouldn't be likely to use this configuation today except as an retrofit to an old professional setup. 8X8 Matrix switches are expensive, starting at $500 and going way up for an 8x8 switch. Thus, it is cheaper to do the switching digitally inside a computer that can provide more functionality, as well. A mix of analog (composite/component) signals and digital (HDMI) signals complicates the switch matrix. This example shows how professionals have traditionally handled the interconnections so that you can dub from any format to any format. A less expensive, smaller matrix switch may be needed for some retrofits.
And below is how a professional might hook things up today. One box works as a Digital Video Recorder, DVD/HD-DVD/Blu-ray recorder and player, CD player, media player, internet TV player, video games, web browser, and general purpose computer. A VCR is hooked up for dubbing materials from that obsolete format. Full 6 channel surround sound. Note the trend towards fewer boxes, thwarted somewhat by satellite/cable providers who fail to provide standard signals. Since TV tuners are replaceable modules, no DTV converters are used. This system allows simultaneous viewing or recording of 4 separate programs, 2 from over the air and two from satellite/cable. Recorded programs are saved on the hard drive and can be archived to DVD, HD-DVD, or Blu-ray. This system would provide full HDTV viewing when a suitable monitor was used. If the capability to dub onto VHS is still needed, video and audio outputs could be connected to the VCR as well. A USB or traditional turntable and cassette deck can be connected to convert old audio recordings to modern formats. MythTV is often used as the software on such a system. Copy protected outputs from cable/satellite boxes and HD-DVD/Blu-ray, however, are a serious problem.
The government does not require that devices be RoHS (reduction of hazardous substances) or lead-free compliant. However, some manufacturers may provide RoHS/lead free compliant devices because they are manufactured in a country that has regulations requiring it or they intend to sell the device, or variant models, in jurisdictions that require compliance, or because they have already tooled up for RoHS because they normally sell to such markets. RoHS/lead-free compliance is not necessarily a good thing.
The environmental impact of an electronic device includes:
The impact of extracting and processing the raw materials used in manufacturing. Silver is used in lead-free solders and silver mining and processing generates large amounts of pollution. This plus any other pollution in manufacturing, is the embodied polution.
Waste due to unusable components. Lead free electronic components typically have a shelf life of only 6 months to 2 years. If they are not soldered onto circuit boards by that time, they become waste and their embodied energy, CO2, and pollution is wasted.
The energy used in manufacturing the product, its components, and raw materials, called embodied energy. Along with the embodied energy, is embodied CO2 (greenhouse gas emissions) which comes from the energy used in production as well as any processes which release greenhouse gasses. The embodied energy in an electronic product typically exceeds the energy that product will consume over its useful life. Lead-free circuits have reliability problems which may significantly reduce their useful life, requiring replacement which incurs additional expense for the consumer and additional embodied energy/CO2 /pollution. If the useful life of a product is halved, the embodied energy,CO2, and pollution are effectively doubled.
The energy consumed by the device during operation. Just the out of pocket expenses for the energy consumed often exceed the purchase price of the product, to say nothing of the environmental impact.
Side effects during use.
End of life effects. Pollution due to improper disposal/failure to recycle.
Effect of retooling. Equipment that was used for assembling lead based circuits cannot be used for lead free circuits. Therefore, all the embodied energy/CO2/pollution for new equipment needs to be considered.
To the extent that DTV converters preserve the useful life of existing TVs, they may have a positive environmental impact. However, contributing to the proliferation of separate A/V components is a negative impact compared to DTV tuners integrated into other products. In other words, if you were allowed to purchase, for example, a DVD recorder with built in DTV converter functionality, the environmental impact would be lower than if you purchase a DTV converter and a DVD recorder. Thus, the narrowly limited coupons may entice you to make a poor environmental choice.
An article in Home Energy Magazine and an LBL report give the power consumption of video appliances (1999 figures).. TV power consumption varies with size, among other factors, but a typical 19-20” TV consumes 68Watts when on and 5.1 watts in standby (a typical energy star TV uses 1.7W in standby). A typical digital cable box is 23 watts whether on or “off”, about twice the consumption for an analog cable box. A typical satellite TV box, uses 17W active and 16W standby.. 95% of the VCR's power consumption occurs when it isn't playing or recording, in other words, most of the power consumption occurs when it is in standby or switched on to permit signal passthrough. Even a typical energy star VCR uses 3W in standby out of 4W allowed and a non-energy star model twice that. DVD players use 2 to 7W when “off”. Digital TVs typically consume twice as much power, on or off, as their analog counterparts (though the typical digital TV at that time was probably larger and improvements in IC designs may have improved things since then). Cable and satellite boxes are expected to be on so they can download program listings, software updates, etc. Thus, the devices that most need to be switched off may not be able to be.
Because of the embodied energy, replacing an older unit with a newer energy efficient model may not be an improvement. Thus, you should consider the energy consumption of new devices and look for ways to minimize the power consumption of existing devices. Adding a seperate power strip to turn off devices rather than leaving them in standby may help though some devices will lose time or settings when turned off completely. Also VCRs and DVD recorders that need to wake up automatically to do unattended recording can't do so when power is removed. If you use electric heat (excluding heat pumps), power consumption in the winter may be a moot point as it may simply reduce the on time of the electric heaters.
Cost
Copy protection
Undecided outcomes of format wars. Nobody wants to buy a player and movies, only to have it become obsolete. And without a player and new movies, that investment in HDTV displays is largely wasted.
Tired of the upgrade treadmill
Many people who purchased HDTVs got burned because they didn't have HDCP (copy protection).
Many people don't care that much about high definition. Some don't see an advantage in seeing a movie on a big screen vs on DVD (and DVD sales are almost three times theatrical sales). And people are watching a lot of content that is less than DVD resolution. Youtube, portable media players, etc. Cory Doctorow posted a list of movie stars who look like crap in HD along with a scathing article about high def.
Media companies have a long track record of trying to suppress or cripple new technologies on the grounds that it will hurt them; in fact, they usually profit from the the very technologies they tried to suppress. They tried to suppress the VCR, yet they now make more money from home video sales than they do from theatrical screenings. They tried to suppress radio broadcasts of music; now they pay bribes to radio stations to play their music. Today, they impose copy protection on video cassettes, DVDs, HD-DVD, and Blu-ray formats as well as DVI,HDMI, and firewire to maintain their psychopathic price gouging. They gouge consumers and then have the nerve to call consumers criminals when they don't bend over. They have gotten corrupt politicians to pass laws infringing on consumers fair use rights. Consumers would, ordinarily, prefer to own originals. Yet, with copy protection, they have created the peculiar situation where a copy is more valuable than a defective (copy protected) originals. If you can't make fair use copies to take with you when you travel, for use in the car, or for use by kids (who tend to destroy things) and have trouble using free software to play the materials, then what is the incentive to buy? Furthermore, many consumers have ethical problems with supporting criminal media corporations, even if they want to support the artists. At $6 without copy protection, DVDs will practically jump of the shelves, at $30 with copy protection, they sit there looking lonely. And they have been sitting there looking lonely – the industry is upset about the sales slump. But instead of accepting that they themselves are the problem, they are attacking consumers. There is a reason that Wal*mart accounts for 40-45% of DVD sales – because even a few dollars makes a big difference in sales volume. You can make more money selling 10 million copies at $10 than you can selling 1 million copies at $20. They tried to impose this on digital TV transmissions, via the broadcast flag but were shot down, but they continue to try to infringe on your rights by reintroducing the broadcast flag. Join the EFF (it is free) to protect your rights from further infringement. I owned a DVD player for a couple years before the CSS copy protection was broken on DVDs, during which time I purchased a total of about 3 DVDs. After that, I bought hundreds. Then they passed the DMCA.. So, they lost a couple hundred sales due to copy protection, from me alone. And I am not going to be buying Blu-ray or HD-DVD disks either, because of the copy protection. If I can't play it on my PC using my choice of software, I am not buying it. I rent more than I buy, these days. They are particularly hard on digital formats under the false premise that digital copies are perfect copies. They usually aren't. When copying a double layer DVD, do you think people pay $2 for a double layer disk? No, typically they compress the video (losing quality) to fit it onto a $0.25 disk. And with Blu-ray and HD-DVD, the cost of blank media is even higher. Are off the air recordings perfect copies? No. Even if you have prefect reception, the content is censored before broadcast, there are often commercial breaks, and there are often station ID bugs in the corner of the image. Computer software used to be copy protected; that went the way of the dodo bird. They even figured out how to make money by encouraging copying. It is technologically impossible to prevent hard core pirates from copying stuff; instead, companies only hurt their paying customers.
Just a few of the ways copy protection has personally affected me:
My TV/VCR combo wouldn't work with a DVD player
When my last TV died and I substituted an RF only model, guess what. My $200 Sony VCR (built post-macrovision) would not pass through the copy-protected DVD signal unmolested, even though it wasn't in record mode.
Problems playing DVDs on my computers with open source software
Problems transferring my VHS tapes to DVD to save space.
Problems with setting up a HTPC.
If you haven't been burned by copy protection yet, or just didn't realize it, you will be.
Someone on avsforum found the FCC filings on a number of units and I added some. These are very hard to find unless you know the FCC ID number. They are also hard to find when the FCC site goes down. FCC ID numbers are frequently printed on the outside of the enclosure; if you have one send it in. These links point to manuals, inside and outside photos, compliance test reports, etc. FCC search – these were found under equipment class HID-Part 15 TV Interface Device
BEJ9QK00710 Zenith/Insignia
VZRCAX-01 Daytek/CASTi CAX-01
C5F7NFD099 Daewoo DAC-100/200/300
VFX2007122901 Coship N9900T
UVD20071228001 Shenzhen MTC AT2016 (Alpha digital/AMTC) (includes schematics) (note: this says “RJTECH TV SET-UP BOX RJ900ATSC” on the front)
Satellite Receiver: U4J-MDV850T Motorola MDV850T
Satellite Receiver: U4VIPRO2000 SATFOX
Satellite Receiver: TL9PREMIER16
Satellite Receiver/DVR: 06ZR16 Humax/Timco Directv plus DVR
Satellite Receiver: SVM-PANSAT250SM Global Technologies
Off topic: Shen Zhen MTC DVD Rewriter UVD200612AMTCDW18 with schematics
LG LGDT1111 System On Chip with Demodulator/Decoder. Specifically targets CECB market but not exclusively. No datasheet but there is a little blurb here and here
Zoran ZR39741 (SupraHD 741). [Product Page] No real datasheets without NDA. Reference design looks a lot like a CECB. If your jacks are in the order ATSC RF in, 3 RCAs, one ??, RF out, ch ¾ switch, and Smart antenna, you might be looking at a reference design with little or no modificatin.
Zoran ZR39740 (typo?)
Broadcom BCM3543 [Product Page] [Product Brief]
Auvitek AU8515
MediaTek 5xxx
Ali M3601C (used with MediaTek 5xxx)
Micronas DRXJ33
R8A66973RP
STV0373
TVP9007 [presentation]
RF Tuner/Modulator
Sanyo UBA00AL (pin compatible with LG TDVG-H051F?) [datasheet]
Thomson DTT76850 [Product Page] [Product Brief] (available in version with passthru) (datasheet found in one of the AT2016 exhibits at FCC).
Thomson DTT75852 Version with passthrue.
LG TDVG-H051F [datasheet]
LG TDVG-H052F
LG TDVG-H151F
LG-TDVG-H151G with passthru?
Microtune MT2131 [Product Brief] No modulator, no passthru
Microtune MT2132 (typo?)
FD0807AT3
LG Tuners link (TDVG series not found)
TVP9900 datasheet
LG 6th generation chip press release
There is a thread on avsforum about hacking the boxes.
Smart antennas are mostly vaporware, at this point. There are very few smart antennas. Channel master 3000A Smartenna isn't one. DX Antenna DTA-5000 is one - though it is only rated for green zone?
Technical info:
Smart antenna connections comply with CEA-909-2002 or later. Pulses are sent at 8Khz (125us). A logic 0 is encoded as a pulse that is high for 41.7us and a logic low is encoded as a pulse that is high for 83.3usec. Timing should be within 5%. A special wide pulse (375uS out of 500uS) is used for power up and reset and preceeds the start bit. signals are 5V ( <1V is low and >2V is high. This is TTL/CMOS compatible but the recommend drive is an open collector NPN transistor with 1K ohm pullup (so the antenna can send signals back) and the antenna has a 2200 ohm load to ground. The TV may optionally sense the load resistor to determine if a smart antenna is connected. Connector is a 6 pin modular plug with an offset tab. Pin 5 is data, pin 2 is 12VDC (+/-10%, 150mA, 200mV max ripple, short circuit protected) from the TV to the antenna, and the others are ground.
Here is a sample bit stream sending: 10101010101010. Each dash or underscore represents one third of a bit time (41.7us):
_____________---------___--_--_-__--_-__--_-__--_-__--_-__--_-__--_-____________________ Idle Reset sb 1 0 1 0 1 0 1 0 1 0 1 0 1 0 Idle
Mode A is pretty simple. Reset pulse, Start bit (1), 2 bits for antenna selection or coarse direction, 2 bits for fine direction, 1 for polarization, 2 for preamp gain, and 7 bits for the RF channel number, then the line sits low at 0V for at least 10ms until the next transmission. The master may exhaustively try all 128 combinations of the first 7 bits during setup (auto mode) to find which works best for a particular station and remember that or may let the user control the bits (manual mode).
Mode B is more complicated and allows the antenna to send back a 10 bit status word and the initial handshake involves sending a channel number of 0 and waiting for a reply with the antennas program number. If it receives a reply and understands it, it sends a word with channel number 1. If it doesn't, it sends a channel number of 0. If the handshake fails, both ends revert to mode A.
ANSI CEA-909A-2007 defines a way to send these signals over the same coax that carries the video.
A backwards wired cable (straight thru vs crossover) is likely to cause damage and may damage more than the smart antenna interface as 12V can be applied through protection diodes to the 5V supply.
There seems to be no provision for allowing more than one TV to share a smart antenna with a single cable. It is possible for a single smart antenna to have multiple antenna connections and one smart interface for each. Which direction, if any, a smart antenna points and what the gain is if it doesn't get a smart antenna signal is anyones guess; so they may not be usable in a pinch with non CEA-909 TVs.
Official List of Coupon Eligible Converter Boxes
shopLocal may be helpful in determining which boxes are available at large retail chain stores in your area. Probably won't tell you what is available at independent retailers.
Solid Signal has may models of digital converters available. So does FreeDTVShop .
Find the direction to TV transmitters and an estimate of how good an antenna you need at antennaweb or TV Fool . The FCC will also let you look up some station info.
HDTVexpert has some CECB reviews.
Tivocommunity has a poll on “which box would you choose”
EngagetHD converterbox news
ezdigitaltv has info on many of the boxes.
NTIA coupon statistics
Charlottesville/Harrisonburg local thread on avsforum . Find more local threads here .
Consumer reports did a very poor quality comparative review of 16 CECBs. Very little detail and they had no idea what to test for. They obviously didn't do their research and hadn't read this page or avsforum. No mention of the recently fixed (but still present in some stores inventory) left channel audio bug. And one of their best picks gets poor reviews at avsforum.
Evaluating Digital to Analog Converter Boxes for Users of Captioning thread on avsforum.
Product and service names are trademarks of their respective owners.
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