1. Home
  2. Electronics Repair
  3. JVC AV-27790

JVC AV-27790

Hello, all. After 11 years of trouble-free operation of the subject TV the following has occurred within the last two weeks:

The set would periodically lose vertical sweep (single bright horizontal line). Vertical sweep would often be absent upon power-up. Lightly bumping the cabinet would often restore the sweep for the rest of the evening's viewing but return the next day.

The set finally quit altogether with the power cycling endlessly on then off until the line cord was unplugged. There was a very pronounced burn smell emanating from inside the cabinet.

I removed the back of cabinet and as best my olfactory sense could determine the burn smell is coming from what appears to be the RF enclosure of one of the tuners (the set has two). There does not appear to be any evidence of burned components elsewhere on any of the three circuit boards.

Why the tuner would have anything to do with vertical sweep failure is confounding. The suspect RF enclosure/assembly is located at the top of the following vertically-mounted circuit board, which is marked (on its underside) as follows:

At top left of board - JVC PWS 96.5.20 SOMEYA

At bottom of board - CKF0426-AS1-1 CMK-81X

Any help in facilitating repair would be greatly appreciated. Thanks so much for your time and comment. Sincerely,

Reply to
J.B. Wood
Loading thread data ...

J.B.Wood: If you would have had this fixed before it quit altogether a shop probably could have done the repair for about $40 to $60 or so.... resoldering connections near and around the vertical deflection output circuitry and flyback derived B+ supply and may replacing some high ESR electrolytics.... now that the television has quit altogether and there is a burnt smell the repair and parts price will be much higher and extent of the repair will be much more involved.

television to start with it sounds to me like you are way over you head on this one. My advice is that you take it to a repair shop for at the very least a repair cost estimate so you can make an intelligent repair deciesion with real numbers from a real tech who opened the set and make tests and measurements. If you want to further investigate a DIY repair you should go to the website for this newsgroup at

formatting link
There, with some search time, you will find a wealth of troubleshooting, testing, repair and IMPORTANT SAFETY information regarding television repair proceedures. Best Regards, electricitym

Reply to
electricitym

Thanks for the response! You make some excellent points but I doubt a TV repair shop these days spends a lot of time troubleshooting and soldering at the board component level. There's just too many surface-mounted components to deal with. I suspect if the shop can trace the problem to a board assembly it becomes a swap out issue. Then there's the issue of whether that board is available for an 11 yr old set. If that faulty card cannot be replaced then the shop would probably say the set's not repairable (or alternatively put, "you wouldn't want to spend what it would take to put the set into working order").

I was hoping to get some insight into what board(s) might be at fault in my set and then attempt a swap out. Sincerely,

John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory

4555 Overlook Avenue, SW Washington, DC 20375-5337
Reply to
J. B. Wood

Analog TVs have ALWALYS been repaired at the component level, including smds. No big deal to fix for a trained technician.

Your TV has no replacable "modules". It is component level only. No boards are swapped out.

Typical carry in charge for a JVC with a burned vertical circuit is under a hundred dollars complete using OEM parts.

Reply to
str00ntz

This set is rarely, if ever, repaired by replacing a board. The repair should be very straightforward for most TV techs. Your assumptions are faulty. You could spend several hundred dollars to buy the board, if it is available. The repair should not be much more than $100 at the component level. As you were told, you might have made it much worse by not dealing with the very common intermittent solder connections until the more severe failure occured. Get it to an experienced shop.

Leonard

Reply to
Leonard Caillouet

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.