Hi
I picked up a nice looking RX-V1071 previous owner stated suddenly stopped working will not power on.
After a few trials got a message on the screen PRT 234H is all I could see, it shut down within 3 seconds, can not get it back on screen again.
Does somebody know where to start looking, I read in service manual DC output too high in Power Amp, but I read some documented yamaha repairs, most of the time amps are OK, often bad solder connections because of heat problems, I think the amp was also used as a cat sleeping area.....might be the cause, what boards to check first?
Cheers, Tojoko.
I picked up a nice looking RX-V1071 previous owner stated suddenly stopped working will not power on.
After a few trials got a message on the screen PRT 234H is all I could see, it shut down within 3 seconds, can not get it back on screen again.
Does somebody know where to start looking, I read in service manual DC output too high in Power Amp, but I read some documented yamaha repairs, most of the time amps are OK, often bad solder connections because of heat problems, I think the amp was also used as a cat sleeping area.....might be the cause, what boards to check first?
Cheers, Tojoko.
Just for information, took out most of the PCB's, checked regulators, one of them showed a short, a 7912, I replaced it, funny enough measured out of pcb, no short, measured new one in pcb, no short????? A few solderings looked not good, so I resoldered all of them.
Will assemble it tonight and see if it makes a difference...
Will assemble it tonight and see if it makes a difference...
Just informing about progress repair....just partly build up the amp, with new 7912 and resoldered pcb's, no power, in diagnostic mode a small explosion from a 0,22 ohm 1 watt metaloxide resistor that protects the circuit....checked rectifier, not good, voltage drop only 0,2 volts, should be around 0.6 volts, Will replace broken parts, I hope it was only rectifier problem....if anyone knows better, please feel free to share the knowledge...
More info on repair RXV171, found short on the 7912 board ( Video board 2) waiting for parts, checked Sanken power Transistors for shorts, none found.
Some more trouble ahead, replaced all suspect parts, now unit will switch on and off continuously just by plugging in 230???? No switch, no remote, does anyone have a clue what causes this? I think something wrong with power pcb, , could it be diodes? Will take it out this weekend and check all diodes on the pcb.
Next...got 2 plugs mixed up, sorted that now the amp still not starting up, in diagnostic mode, I get PS PRT 0 L, so another problem, or caused by previous problem PRT 234H, till now nobody came up with helpful suggestions...
Cheers, Tojoko.
Cheers, Tojoko.
As per the service manual, you've lost a power supply rail, down to 0% (of 5V). Maybe failed rectifier, start with the +/-5, 12V,,, regulated supplies
Hi, I got that wrong it stated DC PRT 0 L, now after a few more trials it is back to DC PRT 196H....
Found another problem what can cause the PRT xxxH on the main 2 board was dirt that was conductive over the input of LB-L and another pin, after removing the dirt no short, but stil same problem, I think short affected one or more parts, so will try and check the parts on Main 2 and 3.