View Full Version : Jvc Av-27f476


radiotvnut
03-05-2008, 08:01 PM
I was cleaning out the basement and found this 27" flat screen CRT JVC AV-27F476. I got this from the local TV shop a few months ago and they claimed it was struck by lightning. The diode across the power relay is shorted; but, there is other problems. I bypassed the relay to see if the main power supply works and it does not. Has anyone had any experience with these models or know where I can get a schematic at a reasonable cost. The Sams is 5155; but, they want $27 for it and I don't want to sink that much in a schematic for a set they may wind up at the dump. As you know, lightning damaged stuff can be simple or it can be problem after problem. Any help will be appreciated.

dr.ido
03-06-2008, 01:05 AM
I'm not familiar with this particular set, but in most of the surge damaged sets (where the surge got in via the mains lead, not the antenna lead) I've found the damage is often confined to the primary side of the power supply. You'll usually find shorted diodes, open resistors and sometimes shorted caps. The chopper IC/transistor may also be bad.

In some sets bridging the relay isn't enough to get the main power supply to start as the standby power supply also provides a startup signal to the main power supply. If the standby power supply is a conventional transformer rather than a switcher the primary may be open.