I have a magnavox rear projection tv, about 3 yrs old, but rarely used. All of a sudden the picture went black, no chanel number, cant use the menu, just completely black. Model number 51mp392h/17. I looked at the trouble shoot stuff, not none of it applies. Any ideas?? Thx!
The manual for Philips/Magnavox 300 series digital rptv chassis is here:
http://www.techlore.com/download/22580/DPTV305.pdf/
Basic safety and dead condition troubleshooting info here:
Troubleshooting a TV For a Dead Condition by Larry Dillon:
http://www.techlore.com/article/14476/Troubleshooting-a-TV-For-a-Dead-Co...
These sets have a repair history of coolant leaks and broken solder joints, which are worth checking for by doing a thorough visual inspection before you start replacing parts. shorted converence ic's may have burned a few related resistors, they can be seen with the boards out. Power supply problems are less common but not unheard of.
I have already gone over the entire board and checked for broken solder joints, and the crt's are dry as can be..no leaks, no residue. I have also checked the convergence resistors and they are fine too! thats why i am guessing the STK 392-120's are to blame -the also seem to be SUPER HOT when you feel the heatsink after only 2 minutes of powering the set on. Would shorted stk IC's cause a video mute problem? I can see the crt's are all glowing red at the base like they should, but they arent doing anything else. Audio is fine.
you can remove the convergence ic's and briefly power up the set.
If sucessful replace with verified genuine sanyo chips that the manual lists for your model.
If not, time to get the isolation transformer and multimeter out.