The DTV transition: The low-down on analog pass-through
Most TV stations must stop broadcasting analog signals on February 17, 2009, but some stations don't have to switch completely to digital broadcasts. Low-power TV stations, TV translator stations, and so-called Class A stations can continue broadcasting analog TV signals well after the deadline. If you're in an area served by such a station, you'll want a DTV converter box that can handle both digital and analog signals. Of course, if you're not able to receive any digital stations, there's no rush to buy any converter box, and we anticipate there being a greater assortment of boxes with analog pass-through in the not-too-distant future.
Low-power TV was created in the early 1980s to provide locally oriented or specialized programming to smaller rural towns or small communities within urban areas. TV translator stations boost and re-broadcast the signals of full-power stations to communities that can't receive them either because they're too far away, or because mountains or uneven terrain inhibit reception. Class A stations are a class of low-power stations that are required to air a certain amount of locally produced programming each week.
The vast majority of TV broadcasts are from full-power stations that will switch to digital, but nearly 7,000 low-power and translator stations provide free over-the-air TV programming to viewers. Although they will one day, too, have to make the switch to digital, currently there's no firm timetable for that transition. Therefore, if you're in a market currently being served by such a station, we recommend you get a DTV converter box with "analog pass-though" capability. These boxes allow analog TV signals to pass through the box without being converted to digital so the TV's analog tuner can receive and display them. We recently ran preliminary tests on one of the early pass-through models, the Philco TB100HH9. We'll be posting that review here shortly.
There are a few ways to determine if you're being served by one of these types of stations. Most low-power stations typically have call letters that end in –LP (such as WAOH-LP); some have five characters starting with the letters K or W, followed by two numbers and two additional letters (W35AX, for example). A translator station uses a similar designation, with its channel number in the middle of its call letters. You're viewing a translator station if you're watching a full-power station but have to tune to another channel to watch it. And Class A stations can typically be identified by the use of a –CA suffix. The National Telecommunications and Information Administration (NTIA), the agency administering the DTV converter box coupon program, has online a complete list of low-power and translator stations.
According to the NTIA, there are currently six approved converter boxes with analog pass-through capability. They are:
- Digital Stream DX8700
- Digital Stream DSP7700T
- EchoStar TR-40
- Magnavox TB-100MG9
- Philco TB100HH9 (seen at right)
- Philco TB150HH9
The NTIA maintains a list of all approved converter boxes online. (Models with analog pass-through have an asterisk next to them. We've previously previewed three DTV converter boxes (without analog pass-through): the Magnavox TB100MW9, Insignia NS-DXA1, and Zenith DTT900 (seen above, left). For more information on what else you need for digital TV on your analog set, see our previous post, "How to use a converter box & antenna to get DTV."
If you've already purchased a DTV converter that doesn't have analog pass-through, you're not completely out of luck. You still may be able to get analog signals to your TV by using an antenna switch or 2-way splitter. Use a splitter if your TV has separate audio/video inputs. Just connect the antenna feed to the splitter, and run one cable from the splitter to the RF input on the TV and another from the splitter to the digital converter's RF input. Connect the converter's A/V output to the TV's A/V input.* You can watch the analog programs by changing channels using the TV's tuner. When you want to watch a digital channel, just switch to the video input.
For TVs that only have an antenna input connector (no separate video inputs), you'll need both an RF antenna splitter and an antenna A/B switch. The splitter should be connected between the antenna and converter box, with one cable connected to the DTV converter box's RF antenna input, and the other going to one of the inputs on the 2-way A/B switch (effectively bypassing the converter). Then run a cable from the converter box's RF output to the second input on the A/B switch. The A/B box's single output is then connected directly to the TV's RF (cable) antenna input. When the A/B switch is on the "digital" (A) side so it's receiving the converter box's signal, tune your TV to channel 3 or 4 to watch digital programs. When you click the switch to the "analog" (B) setting, you'll be able to view any available analog programs by changing channels on the TV. The downside is that you'll have to manually switch between the two inputs on the A/B switch every time you want to switch from an analog channel to a digital one.**
—James K. Willcox
* April 9, 2008 UPDATE: In a previous version of this post, we had inadvertently misplaced a line of text describing the correct procedure for using a converter box with analog pass through.—Ed.
** April 11, 2008 UPDATE: Additional information was added to help clarify how to use an A/B switch with a converter box.—Ed.
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Posted by: Gary | May 30, 2009 8:06:43 AM
I was looking at a Weingard converter that would run off batteries, but they have discontinued this model. Anyone know of another brand that makes a battery powered converter. The Weinguard used a d cell battery pack or cig. lighter adapter.
Posted by: Paul Eng | May 13, 2009 2:21:57 PM
To: Everett Whitney
Thanks for the catch. I really should have searched the Net to see if the Samsung unit was still available before pointing K Andrews to our review of it.
Still, my point is still valid. Such "DTV boxes" are (sort of) a "different animal" than the $40 coupon-eligible DTV converter boxes we discuss here in this post. And, for most people that are interested in DTV converter boxed are for the purposes of converting digital to analog signals.
Again, though... Thanks for the catch!
-PE
Posted by: everett whitney | May 13, 2009 3:47:01 AM
TO: Mr. Paul Eng, Sr. Web Editor, Electronics
A sort of "F.Y.I." perhaps ?
It seems in recent "searching"that the mentioned external Samsung digital tuner unit is no longer available (some used still remain).
That would appear to only leave those versions from TIVO - with their attendant $13/mo fee - as about the sole source for those with a HD-Ready TV.
For what it's worth . . .
everett
Posted by: Paul Eng | May 12, 2009 11:19:26 PM
To K Andrews:
What you propose--a DTV converter box that outputs digital TV signals to a monitor--wouldn't (technically) be a "converter" box, then, but an external digital TV TUNER.
Yes, a DTV converter box does have an ATSC tuner built-in. BUT, the purpose of such boxes is to CONVERT those signals into an ANALOG signal (and down-convert it from HDTV resolutions of 720p or 1080i to 480i) so that older non-HDTV sets can still receive over-the-air broadcasts after June 12.
As many people have mentioned, the whole DTV converter box is meant to be a "low-cost solution" to help ensure that those with ANALOG TV sets -- those with NO DIGITAL inputs or capabilities -- will still have access to news and information broadcast over the public (and federally-regulated) airwaves.
Adding a digital output, while technically possible, would be added expense for DTV box manufactures. And yes, it would probably be JUST a few additional pennies... But it would also be an added feature that would be useless except for those who have a computer model or an "HD-Ready" TV -- again, situations that the DTV converter box program (and the $40 government coupons meant to cover the DTV box cost) weren't meant to address.
By the way, if you ARE looking for a set-top box with a digital ATSC tuner AND digital outputs, we did look at one such box last year. See our First Look at the Samsung DTB-H260F:
http://www.consumerreports.org/cro/electronics-computers/tvs-services/non-digital-tvs/digital-converter-boxes/samsung-dtb-h260f-first-look/overview/samsung-dtb-h260f-first-look.htm
Hope this helps.
--Paul Eng, Sr. Web Ed. (Electronics)
Posted by: K Andrews | May 12, 2009 2:56:26 PM
I would be more interested in a digital output feature than analog pass thru. The converter box already has a digital tuner inside, right? So why not output the digital signal (DVI, HDMI) so you can plug the box into a monitor?
Posted by: everett whitney | Apr 24, 2009 6:55:49 AM
TO: N.C. - " Zenith Pass Thru ..?"
Essentially - yes - just keep the Converter electrically 'on.'
BUT - do be aware that very shortly - that 'feature' or attribute becomes MOOT !
Except for repeaters on some PBS organizations & very, very small private TV Stations temporarily remaining on analog broadcasts longer, come 13 of June - all will be strictly DTV !
In the final analysis - even C.R. has recently stated ".... Converters are only a temporary solution in order to continue using an older CRT set ... "
These are certainly NOT a viable, long-term or permanent FIX.
After a very short interval, several failures of Converters, their inherent shortcomings & tribulations, MANY will realize that there will be the need of a new HDTV for entirely-satisfactory viewing!
Posted by: N C Bradley | Apr 23, 2009 5:55:22 AM
Does analog pass-through( Zenith DTT901) just mean...it allows the analog signal through WITH-OUT having to use a splitter? Do I have to use both the TV control(analog) and the Converter control(digital) or will the pass through digital control work with both analog and digital signals? Thanks. Neil
Posted by: everett whitney | Feb 11, 2009 6:48:34 PM
TO: Kris - " My Cable Company isn't sending the (dot) ..?"
That's perfectly fine - for you ARE exactly as prepared as you need to be ---- No One on local cable needs to do a single, solitary thing - except "continue viewing and / or VCR recording TV !"
No Converter box, no "problems" , etc.. -- you do not even need to re-scan next Wednesday as do all with Converters!
Posted by: Kris | Feb 11, 2009 4:23:00 PM
I have a dtv switch on my vcr. My local cable company will not be sending signals for the "." channels, ie 3.4, 4.6 etc. If I want to view those signals, will I need the box, or just a UHF antenna? I tried scanning for dtv channels as hooked up, but it isnt finding any yet. I know these channels are broadcasting here, as others with tivo or dish are receiving them. Id rather not get a box if I dont have to.
Thanks!
Posted by: Logan Waters | Jan 25, 2009 4:01:31 PM
Just picked up a DTVPal at Sears. All the units there are made in Mexico. Hopefully it's all DTVPal production, and not just this run.
The DTVPal isn't my first choice (no universal remote; no S-video out), but I do try and avoid Chinese-made products whenever possible... no need to help such an oppressive regime in any way.
The converter works fine, BTW. :-)
Posted by: everett whitney | Jan 19, 2009 11:09:57 AM
TO: Mark -17 Jan - " IF Converter has no Universal ....?"
One must continue to use the two remotes separately in your posted instance .... to pay the $100+ funds for a totally-universal Learning Remote will be sort of ludicrous for a federal coupon Converter, a CRT and STILL no "HD" or available Dolby sound .... get a new digital TV, instead !
Posted by: Mark | Jan 17, 2009 5:45:37 PM
If I don't buy a box with a universal remote, how do I adjust the volume of the programming? Do I need to use my TV remote to change the volume on my TV, or do I leave the TV volume set and adjust the volume from the converter box signal? Do all the boxes control the volume seperately from the TV volume (without a universal remote)?
Posted by: everett whitney | Jan 5, 2009 6:30:13 PM
TO: Jerry W-"Very Bad Analog already .... ?"
Welcome to that % of peoples that will be WITHOUT any TV come Feb !
UHF digital reception will Never be received appropriately / consistently IF your existing rooftop antenna/ rotor already does poorly w/ analog! Limit is essentially 35-maybe 40 miles for perfect digital signal reception ... always will be those that get wonderful TV from ... 75 miles .. of course!
But, that's the very unusual ! Plus, digital IS 100 % oerfect or a blank / blue screen!
Posted by: Jerry W | Jan 5, 2009 11:44:25 AM
I purchased a Magnavox TB-100MG9 for use in a very rural area with historically bad analog reception. The scan function on the converter box would not pick all the major network stations in order to program (due to poor reception). The antenna is outside and controled by a rotor to dial in specific stations. The stations are snowy in normal analog mode.
My questions: (1) Is there a converter box available that will let you manually input specific stations rather than using the scan function?
(2)Is there a converter box than is better at receiving weaker signals?
The house is used as a hunting camp so satelite is out of the question since it is vacant a good portion of the year.
Thank you.
Posted by: everett whitney | Dec 16, 2008 5:56:04 AM
TO: Jgnorman - 13 Dec - " CBS-DTV @ Chicago is ???"
CBS-digital IS now at 2.1 & will still be on Hi-VHF Band transmission after Feb ... Your new antenna may Not pick up VHF band.... some are for UHF only.
That federal coupon converter needed to have had .. pass-through, as well.
Posted by: jgnorman | Dec 13, 2008 3:36:04 PM
I just installed a Magnavox TB100MW9 digital converter box along with a new digital antenna to my analog tv. I am now receiving all channels as before along with some new sub channels but cannot get my local cbs channel. I live in Chicago. Does anyone know why not?
Posted by: Lynn M. | Oct 5, 2008 2:49:05 PM
I couldn't get any analog stations with my box hooked to my TV. The directions that came with my Tivax STB-T8 didn't say anything about how to make the analog pass though work. Fortunately, someone on the AVS Forum helped me out, and for the sake of any other dummies out there, this is the missing piece: In addition to fastening the coax antenna cable to RF input on the box, and fastening the red/yellow/white composite A/V cable from the TV to the box, it is also necessary to connect a piece of coax cable from RF output on the box to the RF input on the TV. Place the box on standby and surf channels with the TV remote or TV channel buttons. Tivax provided both the A/V cable and the short piece of coax cable.
I sure wish Tivax had mentioned that in their instructions.
Posted by: Lynn M. | Oct 4, 2008 8:02:46 PM
I just hooked up a Tivax STB-T8 with analog pass-through. I get one digital channel. With the box hooked up, I can't get any of the 6 analog stations I was getting. The directions don't tell you how to get analog pass-through and Tivax doesn't have a number or website to ask. How does one get analog stations on an analog pass-through DTV?
Posted by: everett whitney | Oct 3, 2008 10:40:40 AM
TO: Kim-02 Oct- " A Button for Pass-thru ? "
That's essentially what happens anyway ... the TV Remote must be used in order to "auto-program" & search for any existing analog channels still actively broadcasting - today or in a year.
Posted by: Kim | Oct 2, 2008 2:48:19 PM
With an analog pass-through converter, can it be operated in non-pass-through mode? i.e. something like press a button on converter remote to deactivate pass-through and I use my regular TV remote to flip channels?
Posted by: everett whitney | Sep 30, 2008 8:38:57 AM
TO: ROB - 28 Sept - " Any Chance these are Not China...?"
Sadly, Not a single one!
The very minimum specifications, bid & build by the least of the makers! Do note that none of the top Tier HDTV makers bothered to participate.
Between UHF band will need constant adjusting of any indoor antenna, the expense of an appropriate new outside UHF antenna system, the added problems of obtaining reliable, all-weather UHF band reception, federal coupon Converters will be unsatisfactory for many.
Posted by: ROB | Sep 28, 2008 4:40:42 PM
Any chance any of these are not made in china?
Posted by: Denice Rhodes | Sep 5, 2008 2:31:36 PM
Even with great instructions like yours, some people will still be left behind once the switch is made to digital tv.
Our non-profit, the Urban Progressive Foundation has been actively working with seniors and other groups to provide straight, clear and understandable information to help them through the transition.
Later this week, I will be traveling to Wilmington, North Carolina, where the first full blown transition test-run will commence (if the hurricane doesn't alter plans). If you can't make the trip, allow me to be your eyes and ears. Visit my blog http://digitaldynamo.blogspot.com/ and website www.transition2DTV.com to for more information.
Posted by: Mike | Jun 3, 2008 4:16:52 PM
Canada won't require digital broadcast of its channels until 2011. That's why those of us in a border city (like Detroit) need analog pass through but I haven't found 1 converter in stock anywhere around me. I only have 16 more days and I just started rechecking the local stores. This 90 day restriction, with not all converters being available for purchase, is among the stupidest things our government has done. Why are they making it difficult to get the converters?
At worst, I'll buy a non-pass through converter and hopefully sell it to someone else who gets their coupon later. I would've waited to order my coupons if I had known I wouldn't be able to purchase what I needed.
Posted by: Joseph Held | May 18, 2008 2:32:26 PM
I have a DVD recorder and the convertor box I purchased did not tell you how to hook it up to the other components. I think I've figured it out, but my Panasonic DVD recoreder won't record the digital stations. I have to split my aerial so that the recorder can only record analog. Does this mean that my DVD recorder will be obsolete come February. Also,I get more stations on the digital, but there's no comprehensive TV guide for the programs. Also, I lost a PBS station that I can only see on Analog. I'm not particularly happy about this situation. Any suggestions? I've tried contacting the manufacturer of the convertor box for help, DIgital Stream, their phone is always busy and the website they direct you to is TOTALLTY USELESS! Thanks for listening!