Pioneer Spec-1

With the DBT you can temporary install some 1A's if you have those. Make a note with some tape and attach it to the unit so you remember to replace them before you go to full line power.
I'll find the correct part number fuses at Mouser.
 
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true, I'll build it tomorrow and see if I can find a 1/2 amp fuse, I have 1....hardware stores around here usually don't carry such low amperage fuse
built the bulb tester and it works fine...I had 1 (1/2) amp fuse and 1 (1) amp fuse which I used in conjuntion with the bulb tester.....no fuses blew so I started testing B+ and B- voltages going into the power supply board from the fuse board... I checked pin 1-4-6 on the fuse assy. board....0 voltage on any pin.....I checked pin 6-7-3 on the power supply input....on pin 6 should have +62V reading 0......on pin 3 should be reading 32V reading 0...however on pin 7 I should be reading -63V and I'm reading -184V what the &%#$......Help!
 
Looked again and the 1/2A fuse blew....the bulb went dim when this happened. Using a 75W bulb in the tester....
 
Disconnect the feeds from the fuse board going to the power supply. Pins 4 and 1 of the fuse board, or 6 and 7 of the PS.
Disconnect whatever connection is easiest.
Then recheck using the DBT.
Is the bulb dim or bright?

I'll desolder the pin from the board keeping the wrap intact. With a wide tip on the soldering tool apply the tip to the solder end of the pin. Wait until the solder melts and push the pin to the board.
Clean up the solder. Use your pliers to remove the wrapped pins.
Don't burn yourself.
 
Done, removed pins 6 and 7 on Power supply board, only problem is fuses, I don't have anymore 1/2 amp or 1 amp...all I have are 2amp. I'll have to wait till tomorrow to get some 1 amp fuses...
 
I thought you had some installed?
Did they blow?
If the DBT goes bright and stays bright that means a short is present. Turn the DBT off and investigate.
 
Well. That’s one way of finding the issue.
The short is in the fuse board.
 
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If fuses are still serviceable. Check the DC voltage on the AWR-094 power supply board. Pins 6 & 7. Should be + and - 62vdc. Pin 13 should be 32vdc.
Hi, I replaced the diodes on the fuse board, however I am still getting 0 volts at pin 6 and .2V on pin 7 at the power supply...Pin 13 on the power supply I am reading 55.5V.....I have noticed when I power the amp on the speaker relays click....but the relay ASR-012 on the Mixing amp. Bd. does nothing...Any ideas?
 
built the dim bulb tester, it works great...fuses do not blow, but still no + or - voltageI have found a major problem in the Power supply board. transistor Q4, the case is broke in two at the seam of the case....I'm going to replace all the transistors on the power supply board AWR-094...I believe this is the problem....any feedback?
 
Replace the transistors and diodes if possible. Whatever went through that PS could of weakened the survivors.
Resistors should be checked for value.
 
Replace the transistors and diodes if possible. Whatever went through that PS could of weakened the survivors.
Resistors should be checked for value.
Will do, I have also order new diode and will replace all capacitors.....I'm hoping this fixing the voltage problems..
 
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