Hello, My TV has a problem which has been getting worse and worse. When I turn the TV on, the bottom half of the image is compressed upward toward the middle of the screen. So, if the screen is showing a head shot, you'll see the top half of the head fine, then there's a bright band where the nose is, and black screen underneath that. As the TV warms up, the bottom half gradually unfurls to cover the full screen, but never completely (maybe a half-inch of black screen remains). This "decompression" process now takes almost an hour. I took the back off and adjusted the "height" screw, as well as almost every other screw back there - to no avail. Is this fixable? The TV is an 8 or 9 year old Toshiba, so it's nothing special. But, if it's an easy fix, I'd just as soon repair it. Any ideas? Thanks everyone! Fred Mann
Likely you have (had) dried out electrolytic capacitors causing this, and as they warmed up they slightly improved the picture.
However after running it for some time after it started to collapse can cause additional components to fail such as shorted ICs/Transistors and overheated resistors (as is well known in Magnavox TVs)
Also fiddling with "all the screws" means it is now probably significantly out of adjustment and will require more than a couple simple capacitors replaced, meaning tons of shop time costing more than a new TV would, if you don't have the knowledge of repairing it yourself.
You have an electrolytic capacitor in the vertical deflection output that is drying up. It's an easy repair but you'll have to take it to a professional to find the part and replace it.
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The capacitor probably cost $2 and some time to solder it in. It would probably cost him more than the TV is worth at that age if he took it to a shop.
I was given a TV that had the bright horizontal line across the screen. I heard it had to be rapped on the side to make it work, but finally that didn't help. I knew it was a bad solder joint and had it fixed that night.
Cost of parts real cheap. Amount of labor to do the repair cheap. The cost of checking it out and getting ready to replace the parts, about equal to a new set.
It is a classic problem, and if you find someone who does not like to make enough to live on, they may fix it cheap and that would be worth it, but most shops have a minimal charge and that may be more than it is worth.
And from his post regarding fiddling with knobs inside the set and absolutely no indication of any real technical knowledge, his best option is to take the set into a reputable and qualified servicer for repair. Even with some adjustment screw ups on that set, repair still likely to run under $90 TOTAL. Would have probably been under $75 had he not screwed it up worse by not knowing what he was doing.
But how much is it worth to HIM? If it's the difference between tossing it and buying a new one or fixing it for $50 or $75 and it is in decent condition otherwise, it might be worth fixing.
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*Never* ever fiddle with internal adjustments when a problem occurs, you will often make it impossible to repair at that point because a tech will never know when they've fixed the original problem if it's all out of wack, adjustments DON'T just change on modern sets and don't need to be messed with once the unit leaves the factory.
The original problem was a few bad capacitors in the vertical section, who knows if you'll ever get it right after messing with the adjustments though.
Go ahead and do a Goole Droups archive search at this newsgroup for Toshiba vertical and see what comes up. You might even try the exact model number as well. You will however have to be able to identify the vertical output ic and jungle ic before proceeding. If that is beyond your scope of experience, at the very least consider giving the set to someone who will fix it rather than bin it to keep it out of the landfill a few more years.
You are still more than likely looking at under $75 total repair if you can find a reputable service shop and typically they will warranty the repair for a few months in case of repeat problem.
Thanks for all the replies! As far as the adjustments that I made are concerned - I didn't adjust all of the screws, and the ones I did adjust, I returned to their original positions (some screws are "glued" in place). So, presumably the problem could still be easily resolved if the capicitor is the only problem. Unfortunately, I am unable to identify the "electrolytic capacitor in the vertical deflection output". Are there any diagrams online which would help me identify this, or is it labled on the board? Like one of the posters said, it's a shame to junk an item over a $2 part. Obviously, I don't care if I make it worse, so I'm willing to give it a shot. Can anybody tell me how to identify this part(s)? (Taking it to a repair place is out of the question as the minimum fees around here are $50 bucks or so) Thanks again everybody! Fred
Same thing happened to my 19" Toshiba. Repair was about $125. Was it worth it? We liked the TV and some of the new ones at the time (several years ago) looked like junk. I would probably check the market now before spending that much on repair since a lot has changed TV wise in the last couple of years.
:Hello, :My TV has a problem which has been getting worse and worse. When I turn the :TV on, the bottom half of the image is compressed upward toward the middle :of the screen. So, if the screen is showing a head shot, you'll see the top :half of the head fine, then there's a bright band where the nose is, and :black screen underneath that. As the TV warms up, the bottom half gradually :unfurls to cover the full screen, but never completely (maybe a half-inch of :black screen remains). This "decompression" process now takes almost an :hour. I took the back off and adjusted the "height" screw, as well as almost :every other screw back there - to no avail. :Is this fixable? The TV is an 8 or 9 year old Toshiba, so it's nothing :special. But, if it's an easy fix, I'd just as soon repair it. :Any ideas? :Thanks everyone! :Fred Mann
On a related note (if I may piggy back here), my 14 or so year old 20 inch JVC TV (it was one of the very best 20 inch TVs in 1989 or so) works fine except that the tube has been losing brightness over the last several years. I now have the brightness and contrast set at the highest levels and for most broadcasts it's OK, but for some it's really not bright enough. Is it not cost effective to replace the tube (I assume that's the only remedy short of buying a new TV)? I could get another TV or even go HDTV (I'd like to!), but I'm pretty darn busy already and buying a TV nowadays is a lot more complicated than it used to be. I wouldn't feel comfortable buying a new set/monitor without doing my homework. TIA
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PS This is a JVC AV-2058S with S-Video input and lots of controls.
A Japanese TV that old almost surely has a high-quality Japanese picture tube that can easily last 15-20 years (I have one 20+ years old that's still bright and sharp), so try turning up the SCREEN control on the flyback transformer (2-3" cube of black or grey plastic with thick cable going to the side of the picture tube). This may be accessible through a small hole in the back of the cabinet, but more likely the rear half of the cabinet will have to be removed to gain access. This makes the adjustment procedure much, much more hazardous because of the risk of electrocution, so you may want to make the adjustment only while the TV is unplugged (mark initial position of the control, rotate it 1/8 turn each time until it's bright enough). If you dare adjust the TV while it's plugged in, set it on a nonconductive surface, such as a wooden table. The chassis itself often has high voltage on it, so it must not touch metal, and you must not touch it. Also you must plug the TV into a wall outlet protected by a ground fault circuit interrupter (GFCI or GFI), but this won't protect you against all electric shocks, and GFCIs sometimes fail (test yours just before use). Get a large mirror so you can see the picture or else you'll tend to get too close to exposed high voltage areas and kill yourself. Use a special all-plastic screwdriver made for high voltage work (Radio Shack or an TV or electronics supply will have them; they have no metal except for maybe the last 1/8" of the tip). Do NOT substitute an ordinary metal screwdriver with a plastic handle, and do NOT simply wrap the metal shaft with electrical tape. Wear rubber soled shoes, and keep one hand in your pocket to make it less likely that you'll create a complete electrical path with your body (a path that sends electricity up one arm, through your heart, and out the other arm). Never do this kind of work alone; always have someone else in the same room to call 911 and administer CPR if you get shocked.
Another risk is that the TV may tip over forward and break its picture tube, which will cause shards of glass and metal to shoot out violently. So be sure that the TV can't break (place big pillows in front, or lay it face-down on foam rubber while you remove its back).
You may have to adjust the FOCUS control after turning up the SCREEN since this can make the picture blurry.
If the picture stays dim, you may need to replace some electrolytic capacitors (not that difficult or expensive) or the flyback (impractical, although some old ones are under $20 from
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There are several of those capacitors around the flyback that wear out, and any replacements must not be installed backwards (check original polarity markings on capacitors and circuit board), and they must be rated for at least as much voltage as the originals, but capacitance values can be slightly lower or higher (often double is still OK).
You should be able to find the vertical circuitry because almost every TV's main board is marked off by major function -- power, vertical, horizontal, tuner, chroma, sound, etc., but the markings may be on the other side. Some libraries carry repair manuals, usually "Sams Photofacts." Or you could write down the markings found on the chips of the main board and look them up at
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or
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Then replace all the electrolytics located around any chip that handles vertical output/sync.
Electrolytics aren't expensive if you buy them from the right place, like BDEnt or DigiKey, and you can replace all or most of them for little money. I've found that the lower-voltage ones don't fail that much, unless they're connected to the flyback transformer (many of those are rated for 105 Celcius), while the ones rated for at least
80-100V fail much more often (the one causing your problem is probably rated 150-200V).
With apologies to MC! Yes and also; Cost of materials to fix the problem $10 or less. Possibly only a capacitor and some solder? Time spent and identifying where and how to fix the problem; along with all the tools, test gear and knowhow, cost of electricity and other shop costs, telephone-vehicle costs, liability insurance, substitution equipment and/or parts on hand ..... etc. etc. $60). Time spent talking to customer etc. Priceless! :-)
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