Weird voltages on a twin face Ge side

kurtis1

Member
I built this twin fuzz face from pedal pcb. The silicone side works fine but on the Ge side I can't get less than 8.2v on Q2.


The voltages are wierd all over the Ge side of the circuit. I've tried a different set of ac128 transistors and I get the same results. The voltages after R1 should be 10x what they are. What would cause this? Is C1 somehow dumping voltage to ground? Is that possible? I've attached my voltage readings, a gut shot and a diagram from electrosmash dictating the correct voltages.

Thanks


https://drive.google.com/file/d/11HeCZtQq7UNQSgBajusg15dBdL9xz1_A/view?usp=drivesdk


https://drive.google.com/file/d/11JzXTKd427Umf7C3R2YzHwNdkFP4bMte/view?usp=drivesdk


https://drive.google.com/file/d/11HwKKZ5r85hbMWDtrI2pKyV40K4kqqJr/view?usp=drivesdk
 
Any luck with the Russian versions? I actually bought Pedalhacker AC 128s and have the same problems with the Ge Biasing from the beginning of the post. I'm not as proficient to fully understand the earlier readouts of the transistors, but I'm suspecting the batch I bought might be 'leaky' as well. At this point, I just hope there's a 'verified' source for Ge transistors that work with this kit.
 
Any luck with the Russian versions? I actually bought Pedalhacker AC 128s and have the same problems with the Ge Biasing from the beginning of the post. I'm not as proficient to fully understand the earlier readouts of the transistors, but I'm suspecting the batch I bought might be 'leaky' as well. At this point, I just hope there's a 'verified' source for Ge transistors that work with this kit.
Sorry I haven't kept this thread up to date. I'm a golf course superintendent and I also manage a small water treatment plant so I've been incredibly busy lately. But I did get to try my pedal hacker ac128's and I have the same problem with biasing them. I'm currently using like 21k of resistance to get them biased down to 4.5v

I've just received my Russian p28's on Thursday. I'll maybe find some time later today to audit them and test them out in the pedal.

If they don't work. I'm going to switch that side of the pedal to +9v and try some bc108's to double check wtf is going on... Maybe PNP and NPN transistors just hate being in the same circuit, I don't know...
 
Okay, I pulled out those ac128's from pedal hacker and installed the p28's. And they work awesome!!! They bias with only 7k resistance and they sound amazing. They cleanup very easily with the guitar volume. I don't know why the ac128's from pedal hacker where so shity. So I guess I'll stick with these p28's. I'm finally happy with this pedal.

Thanks chuck for suggesting these p28's
 
Back
Top