Hello,
i received this amp, with blown ps, and one bank output.. Repaired ps, removed the whole damaged bank, and resolderer the other bank, because of bad solder joints..
The problem is now, that it pulls me up the -15V for the op amps.
On the board are only two op amps, they measure ok..
The LM7915 gets hot realy quick. Op amps stay cold. Between +and- on the op amps i measure 9Ohm.. Removed the lm 7815 and 7915.. Anybody has a schematic, where the voltage is used?
i received this amp, with blown ps, and one bank output.. Repaired ps, removed the whole damaged bank, and resolderer the other bank, because of bad solder joints..
The problem is now, that it pulls me up the -15V for the op amps.
On the board are only two op amps, they measure ok..
The LM7915 gets hot realy quick. Op amps stay cold. Between +and- on the op amps i measure 9Ohm.. Removed the lm 7815 and 7915.. Anybody has a schematic, where the voltage is used?
Continue on this amp.
Repaired PS, installed new output transistors, pre stage, and op amps.
I have Pos. DC on the output of that channel, and the other only disorted low signal.
For the first i want to fix the dc.
Iam now at the stage before the bias.
MPSA 92, i have on all three pins rail voltage.
On the side, with the disorted signal, i have rail on base and emitter. Collector is nothing.
Ground is sec. center.
Marked is the collector. How does it should work?
Repaired PS, installed new output transistors, pre stage, and op amps.
I have Pos. DC on the output of that channel, and the other only disorted low signal.
For the first i want to fix the dc.
Iam now at the stage before the bias.
MPSA 92, i have on all three pins rail voltage.
On the side, with the disorted signal, i have rail on base and emitter. Collector is nothing.
Ground is sec. center.
Marked is the collector. How does it should work?
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