Salora sp2

Guest · Posted: Mon Aug 18, 2008 6:32 pm Post subject:

Diode V030 has 1000 Vrms. It is possible that high voltage across the diode cause the fault? Can I measure voltage without load by voltage meter?

torbjorn · Joined: 07 Jun 2007 Posts: 370 Location: Sweden

Have you checked that the entire voltage control circuit works properly?

Try the following:
1) Don't connect the tv to the electrical mains.
2) Connect +5V from a lab power supply to USS (TPS 31, the output from NO04), return to the ground pin of NO04.
3) Connect about +10-11 V from another lab power supply to NO01's VCC (pin 14), return to pin 12 of NO01.
4) Connect a variable voltage to U1 (cathode of VO30) and measure the voltage between pin 5 and pin 12 of NO01. This voltage should change from high to low when U1 crosses about 150 V. If not, you have a problem around VO12 - NO03. It is possible that you also have to connect +12V to the point RO106 - LO31 - CO37 to get the circuit to work, i wonder what the circuit RO106 - VO13 is there for.

Guest · Posted: Tue Aug 19, 2008 5:05 pm Post subject:

I tested power supply using bulb (150 v diode and chopper transistor are taken off). The bulb burn but when I measure the voltage there is only 0,5 - 1 v across the bulb. Is my power supply OK?

Guest · Posted: Thu Aug 21, 2008 4:46 am Post subject:

Voltage in hot line is 135 V. And bulb burn. So power supply is OK.
So there have to be shorted in hot line. I have tested all capasitors and resistors. Everything seems OK. If it possible that flyback transformer could cause that fault?