01-09-2015, 07:34 PM
I tried powering amp without speaker,I just have one 4ohm. bookshelf speaker to test with.
Checked C15-C18 with ohm setting of meter in circuit I get a reading of like 1.504M on all of them.
V3 & V4 you said to minimum setting. I turned them full ccw.
Powered up and still drawing over 1 amp at 50V. I did have volt meter hooked to C13 + and it was reading 18volts when the B+ of amp was at 50 volts.
I unhooked the B+ to main amp and started taking volt readings at power supply again with outlet volts set to 117V. With the main amp out of circuit I can power up with amps staying .1v
I found something that might be the problem,not for sure.
I can get a AC reading on the B1 post which feeds the main amp. It is 25.40v ac. also can get reading on DC setting it is 54Volts.
I don't get any ac readings on the other B+ posts.
On the power board I have replaced all the E-caps, transistors Q1, Q2 ,Q3, the diodes D-2,3,4,5.
and the zener diode D6. I did remove D1- SB-3P and it tests good. I have not changed any resistors. Do you think something on power board is letting ac into the B+ to main amp? Your help is greatly appreciated.
Checked C15-C18 with ohm setting of meter in circuit I get a reading of like 1.504M on all of them.
V3 & V4 you said to minimum setting. I turned them full ccw.
Powered up and still drawing over 1 amp at 50V. I did have volt meter hooked to C13 + and it was reading 18volts when the B+ of amp was at 50 volts.
I unhooked the B+ to main amp and started taking volt readings at power supply again with outlet volts set to 117V. With the main amp out of circuit I can power up with amps staying .1v
I found something that might be the problem,not for sure.
I can get a AC reading on the B1 post which feeds the main amp. It is 25.40v ac. also can get reading on DC setting it is 54Volts.
I don't get any ac readings on the other B+ posts.
On the power board I have replaced all the E-caps, transistors Q1, Q2 ,Q3, the diodes D-2,3,4,5.
and the zener diode D6. I did remove D1- SB-3P and it tests good. I have not changed any resistors. Do you think something on power board is letting ac into the B+ to main amp? Your help is greatly appreciated.