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Is it that hard to make a DTV radio? People would buy them.

B

brian65

I'm at a loss as to why no manufacturer has come out with a reasonably priced portable radio that will pick up over the air DTV audio.

I realize there are some issues that make them more difficult to produce than the analog version, but it seems like no one is even trying.

In a power outage, many AM radio stations are stuck with syndicated programming or sporting events...which provide no information or news. I have a small (11") portable DTV, but it's battery life is only about 3 hours. Also, there's just many times when I just need the audio portion of TV.

Is there any hope they will make something for those of us who don't Wi-Fi?
 
Here's the challenge:

In analog TV, the audio portion of the signal was a completely separate beast from the video signal. Analog TV audio was essentially identical to FM radio, and that's why it was so easy to design a VHF "TV-sound" radio - all you had to do was extend the frequency bands the existing FM section could receive. (That's also why "Franken-FM" channel 6 stations work so well, and why some of them have worked even without any video component.)

But with ATSC DTV, the audio component is completely embedded in the 19.39 mbps bitstream that carries video and data as well. Decoding the full bitstream takes some computational horsepower, which is why your portable TV gets such rotten battery life. The only real difference between that and a "DTV audio" receiver would be taking away the screen.

There's hope, though...the ATSC/M standard for mobile DTV is designed to be received by portable devices with lower battery consumption. If it takes off (and it's still in its infancy), you might finally get the portable of your dreams - though given that lower battery consumption and the fact that it will be decoding the entire mobile stream (including video), there's really no reason that portable shouldn't have a screen, too.
 
FWIW I've been experimenting with a Mobile DTV receiver here.

I'm afraid the battery life is pretty much the same as what you quote for your 11" set. I do think that's probably colored by two factors:

- There is still a display, which I think is responsible for a fair portion of the battery drain. On a radio, you could at least turn off the backlight after a station is selected -- on a TV, of course you have to leave the backlight on all the time :)
- I have a LOT of RF noise in my house -- and live 25 miles from the station -- so the receiver isn't reliably synced to the transmitter. The battery saving features of the mobile DTV standard call for the mobile packets to be transmitted at predictable, regular intervals -- so the RF chip in the receiver can be turned off between them. If the receiver can't reliably sync to the transmitter, it's going to have to leave the RF chip on a lot more trying to find that signal, draining the battery a lot faster.

In other words, I suspect battery life would be significantly better for those who live closer to the station. (and, for that matter, during a power failure when most of the computerized noise generators in your house aren't running!)
 
I have one of the Auvio portable DTV's from Radio Shack. Uses 4 AA batteries and is good for about three hours. It's just for the big bad storms and power outages, but it actually works quite nicely. I think the scree is 5" but it's good enough to watch Bob the weatherman when the power is out and the tornado sirens are going off.
 
I have a small portable I would have used for storm emergencies but it's dismal at best. Compared to the old analog signals I would get it's worthless. I get zero channels! Even hooked up to the big TV antenna that I can get a whopping 1 and a half channels I don't get anything on the portable.

I think they really screwed the pooch when it came to power allotments for DTV. I know I'm not the only one who took a hit when analog was shut down.
 
The power figures for an ATSC (aka DTV) tuner chip are around 1.2 W. The power figures for an FM tuner are around 100 mW.
 
Between the lower ERP of digital signals and the crummy front ends in all the digital portables I've seen, portable television as we used to know it is essentially gone. And that's too bad.
 
RadeoEngineer said:
I have one of the Auvio portable DTV's from Radio Shack. Uses 4 AA batteries and is good for about three hours. It's just for the big bad storms and power outages, but it actually works quite nicely. I think the scree is 5" but it's good enough to watch Bob the weatherman when the power is out and the tornado sirens are going off.
Click to expand...
I bought the RCA DMT335R, a portable 3.5" TV for over-the-air and mobile-handheld DTV broadcasts. http://www.getmyelectronics.com/products/3-5-hybrid-mdtv-atsc-portable-television It runs on 4 AA alkaline batteries or a wall wart. It's a big hit at football games to watch the replays. The whip antenna might have reception difficulties indoors, so you may need to connect an external antenna when taking shelter from severe weather. Keep extra batteries in your storm supply kit in case of any extended power outage. Also available with 7" screen.
 
DTV-Chief said:
RadeoEngineer said:
I have one of the Auvio portable DTV's from Radio Shack. Uses 4 AA batteries and is good for about three hours. It's just for the big bad storms and power outages, but it actually works quite nicely. I think the scree is 5" but it's good enough to watch Bob the weatherman when the power is out and the tornado sirens are going off.
Click to expand...
I bought the RCA DMT335R, a portable 3.5" TV for over-the-air and mobile-handheld DTV broadcasts. http://www.getmyelectronics.com/products/3-5-hybrid-mdtv-atsc-portable-television It runs on 4 AA alkaline batteries or a wall wart. It's a big hit at football games to watch the replays. The whip antenna might have reception difficulties indoors, so you may need to connect an external antenna when taking shelter from severe weather. Keep extra batteries in your storm supply kit in case of any extended power outage. Also available with 7" screen.
Click to expand...

That looks exactly like, and has all the same functions as, the Auvio I bought at Rat Shack for $89.
 
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