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Dear Coby

One of the key tensions in my relationship with Xy has to do with television. To put it bluntly, she’s for it and I’m against it. I long ago gave up the battle to keep television out of our home, but at least we don’t pay for cable or satellite. We get our TV off the air for free. We switched to digital when our old TV got flooded, and we’ve been enjoying high-definition broadcasts ever since.

I use the term “enjoying” advisedly. I’m just enough of a video geek to think the whole technical aspect of getting high definition signals off the air is cool. I can watch a crappy TV show and still marvel at the gorgeousity of the image.

I was mildly horrified when Xy got a portable TV for our kitchen, but that’s another battle I’ve given up on. Her little $16 set will be made obsolete by the impending digital transition. So as a token of my undying love for her and my boundless magnanimity, I decided to get her a portable digital TV for Xmas. Who else can condescend so nicely?

Only problem, as anyone who’s shopped for such a product knows: It’s slim pickings. Portable digital TVs? I could only find three on the market, and they all cost a lot more than $16.

Ultimately I sprang for the Coby TF-TV791 7″. It arrived a couple weeks ago, and since we don’t believe in delayed gratification, it’s been deployed on our kitchen counter ever since.

It works pretty well. The reception is a little funny, as we can get some stations better than with our main TV downstairs, but others are worse. Xy’s just impressed that it’s in color.

There is one major glaring problem.

I’m going to need an illustration to make this clear. Bear with me.

Coby Comparison

A tip of the hat to the talented Jon Rawlinson for sharing this high definition video frame under a Creative Commons Attribution license.

The top image shows a 16:9 high-definition video frame in its proper aspect ratio. This is how HD video should look on a widescreen TV.

The middle image shows how HD video looks on our Coby in 16:9 mode. Note the black bars on top and bottom. As a rule you shouldn’t see bars on top and bottom on a widescreen TV. Note also that the video image is scrunched down, vertically compressed.

The bottom image shows how HD video looks on our Coby in 4:3 mode. Note that the image is no longer scrunched. It is actually displaying in its proper aspect ratio, but it’s not filling the screen as it should. Something is way wrong here.

I’ve written a note to Coby about this:

I recently purchased your TF-TV791 as a Xmas gift for my wife.

It works well except for one technical issue which is frustrating me.

The set displays 4:3 standard definition video quite well. However, it has a problem with 16:9 high-definition video.

I am of course aware of how to switch back and forth between the 4:3 and 16:9 modes using the remote. The problem is that high-definition video is simply not displayed properly. There are black bars at the top and bottom of the screen when viewing a high-definition signal.

As a general rule, there should not be black bars on a widescreen TV when viewing widescreen video. I’ve been able to check the same broadcast on our larger Panasonic television and verify that the signal properly fills the screen without stretching.

Therefore I can only conclude the problem is with the TF-TV791 unit. Is there some way to correct this problem?

I wonder if they’ll get back to me.

Published inConsumerismFilm & VideoGeekyLettersLife with XyPixRadio & TV


  1. Rob W Rob W

    Tweet it. Lot of corps are monitoring twitter for negative chatter. Put up something like “I hate this fucking Coby TV – it can’t even display 16:9 video properly!”

  2. Good idea, Rob. Tweets away!

  3. I have a feeling it is related to a lowend ATSC–>analog converter/chipset in the TV. I’ve seen the same issue with a cheap Insignia ATSC to analog adapter.

  4. Garvey Garvey

    You’re kind of expecting a lot out of a 7″ TV, no?

  5. Garvey: If expecting it to function properly is “a lot” then yes! I am.

    Zeb: I suspect the chipset as well. How can they sell such things?

  6. B,

    The 7″ LCD is probably less than 800×600 and therefore lower than even 720p broadcasts, so the thing has to scale it down.

    Unfortunately I think “Cheap” and “profit” are the keywords here.

    Have you considered a cheap LCD monitor and a tuner box of some kind?
    Or maybe a USB OTA tuner for a (existing) laptop?

  7. B,

    I must say that all I can do is laugh at your … review. I whole-heartedly agree on the desire for less TV and no TV in the house ( a situation I expect to be facing sooner than later) and can only hope that my whole-hearted stubbornness can prevent such an invasion as a kitchen window…although mayhaps my standard “direct exit, sans b-fast” will suffice. who can tell.

    In any event, keep on writing and speaking, it’s enjoyed.

    Tom might check out the classic “The Third Man” if you haven’t: Def. Quality.

  8. Zeb: I really wanted a self-contained unit. Yeah, it’s low-res, but it handles standard definition digital signals just fine. The image fills the screen from top to bottom in 4:3 mode, with black bars on the sides, which is how it should be.

    Tom: Gonna have to watch Third Man again some day. Saw it years ago and it just didn’t click. But it’s highly regarded by so many I feel like I must have missed something.

  9. AWT AWT

    The Coby TF-TV791 has a resolution of 480 x 234. Which is an aspect ratio of 2.05:1.
    A standard HD set is around 1.78:1(16:9 ratio). this is why the picture looks the way it does. Although you would think there would be an option to fill the screen lik ethe 16:10 ratios computer monitors have.
    But the Coby is a 16:8 ratio monitor.
    I’m still thinking about getting this for my girlfriend, only because it’s so small to replace her old tube 5 inch portable TV. The Coby 10.2 inch one seems a little to big for her.

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