Pin 1 of IC 203 also good Signal. Pin 2,3,5,6,7 nothing. IC 102 Pin 13 also nothing. So maybe IC203 damaged?
A little bit confusing, because not everything is marked in the diagramm.
Ok.Signal passing tru C175 (50V,10uf) : minus from that cap is going to Q102m(K30A).
one Pin of K30a is connected to ground, the center pin is going to resistor R105m.
According diagramm it should go to Pin 14 of IC102, but it seems much different. I will recheck.
Ok.Signal passing tru C175 (50V,10uf) : minus from that cap is going to Q102m(K30A).
one Pin of K30a is connected to ground, the center pin is going to resistor R105m.
According diagramm it should go to Pin 14 of IC102, but it seems much different. I will recheck.
Hello, thanks for that video. I will look later. But i think there is something more wrong. Because if i twist and press the transformers, nothing happen. Without rectifiers inside everything is ok. There is no audio at the moment and bad noise.
If somebody may have a diagramm for that pre-amp section for Revision2. I have a diagramm only for newer one.
If somebody may have a diagramm for that pre-amp section for Revision2. I have a diagramm only for newer one.
ok, i think i found. Its going to pin 13 of IC102. There is a ceramic capacitor wich is parallel with Pin 14.
I'm guessing that it's a TL074. Pin 13 is an input to the op-amp. The 4 corner pins are the output pins.
Let's disable the output stage. Discharge the rail caps and Connect a jumper between the collector and emitter of Q10 on the driver board.
Does that change the voltage on that op-amp?
Does that change the voltage on that op-amp?
If you do as you would if measuring the voltage on pin 13 or pin 14, if you let the probe short pin 13 to 14, does the voltage go to 0v?
On Pin1 ive got a Sinewave. Pin 2 and 3 0VDC and no signal
Ive got on Supply about 30Vdc. On all OP Amps. But Input at that Board is only 15VDC
Ive got on Supply about 30Vdc. On all OP Amps. But Input at that Board is only 15VDC
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