Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
|
|||
|
|||
Sony KPR-46EX32 RPTV intermittent picture
I have a 13 year old Sony KPR-46EX32 RPTV. Last weekend the picture
started suddenly going completely black after between 20-90min of operation. I have a service manual and pulled the "A" and "G" boards out on the floor behind the TV. The DC voltages all seem to be ok. A couple times, probing the -135V on the "G" board connector with my DMM has restored the picture. Searching the web, I found a service website for PC monitors that mentions Sony monitors are notorious for having flaky protection circuits that will erroneously disable the HV circuits. Wondered if this could be a similar problem and by probing it I was changing the voltage just enough to reset it. If anyone knows where I should look to repair this, I'd appreciate it. TIA, Randy |
#2
|
|||
|
|||
Sony KPR-46EX32 RPTV intermittent picture
May want to remove the boards and check for poor solder connections on the
boards, while there use an esr meter to check the caps in the powersupply and deflection circuits. Good mag glass and light source will assist in seeing the cracked solder connections. "randy" wrote in message t... I have a 13 year old Sony KPR-46EX32 RPTV. Last weekend the picture started suddenly going completely black after between 20-90min of operation. I have a service manual and pulled the "A" and "G" boards out on the floor behind the TV. The DC voltages all seem to be ok. A couple times, probing the -135V on the "G" board connector with my DMM has restored the picture. Searching the web, I found a service website for PC monitors that mentions Sony monitors are notorious for having flaky protection circuits that will erroneously disable the HV circuits. Wondered if this could be a similar problem and by probing it I was changing the voltage just enough to reset it. If anyone knows where I should look to repair this, I'd appreciate it. TIA, Randy |
#3
|
|||
|
|||
Sony KPR-46EX32 RPTV intermittent picture
Actually this model would be more notorious for bad solder joints causing
this problem. Look for the obvious first. If you get into troubleshooting the protection circuits without some experience you will likely chase your tail. Leonard "randy" wrote in message t... I have a 13 year old Sony KPR-46EX32 RPTV. Last weekend the picture started suddenly going completely black after between 20-90min of operation. I have a service manual and pulled the "A" and "G" boards out on the floor behind the TV. The DC voltages all seem to be ok. A couple times, probing the -135V on the "G" board connector with my DMM has restored the picture. Searching the web, I found a service website for PC monitors that mentions Sony monitors are notorious for having flaky protection circuits that will erroneously disable the HV circuits. Wondered if this could be a similar problem and by probing it I was changing the voltage just enough to reset it. If anyone knows where I should look to repair this, I'd appreciate it. TIA, Randy |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Sony KV-32S40 has audio but no picture | Electronics Repair | |||
No picture but sound on SONY KV-35V36 | Electronics Repair | |||
Sony KV27TS20 Picture becomes a thin horizontal line - Vertical squashed | Electronics Repair | |||
Sony Wega fading to red, then losing picture | Electronics Repair |