Hi, first time posting, I'll do my best to start with some good info, please let me know what I can do better to make it easier for others to help troubleshoot!
I'm breadboarding the Rat (Muroidea) schematic that is shown in this post:
https://forum.pedalpcb.com/threads/muroidea-proco-rat.12237
The schematic I'm using is attached. A photo of my breadboard also attached. The large yellow capacitor near the top left is just for my audio probe. Normally I bypass that when testing with the volume knob, but in this photo I forgot to remove it. That makes no discernible difference in volume whether it's included or not. Let me know if we need more photos or voltage readouts!
Note that I've got a separate little perf circuit I made that provides VREF and that vref is coming into my board on the right at G1. I actually used a different power circuit there from a Wampler lesson. I've tried it with the voltage separator in the schematic, and it made no difference in volume level. It actually produced a weaker VREF around 4.2v (maybe just variance in the parts I used) so I went back to my external VREF module for convenience.
The issue is that it while it sounds right as far as I know, the volume is very low when the Vol knob is maxxed out. It's at about unity when cranked.
I built a vero board rat (I assume a similar/same circuit) and it's in an enclosure. The one in the enclosure is at Unity when the knob is at about 7:30. Turning up that vero build vol knob will get the signal really loud above unity.
I used an audio probe and noticed that on the diode side of R6 my signal is pretty quiet (same volume as when going through the vol pot when dimed) so I'm not sure if the diodes are dropping voltage too much or if there's another problem elsewhere. I've tried swapping diodes for other 1N4148s and the transistor. Currently I have a 2N5457 in there (so does the vero build) and I put a J201 in there and it's the same volume level. The opamp is a OP07.
Some voltage readings on my breadboard:
V+ 9.73v
VREF: 4.84v
IC 1: 9.68v
IC 2: 4.86v
IC 3: 4.37v
IC 4: -.2mv
IC 5: 1.7mv
IC 6: 4.83mv
IC 7: 9.75v
IC 8: 9.68v
R6: 4.82v (between R6 and C7)
FILTER pin1: .682v
Q1 D: 9.74v
Q1 S: 1.225v
Q1 G: 3.7mv
Components I've tried replacing in case they are damaged/defective:
D1
D2
C7
C10
Q1
From what I can gather on other posts, my source voltage should be about right as long as it's above 1v, so I'm just not sure what's up.
I'm breadboarding the Rat (Muroidea) schematic that is shown in this post:
https://forum.pedalpcb.com/threads/muroidea-proco-rat.12237
The schematic I'm using is attached. A photo of my breadboard also attached. The large yellow capacitor near the top left is just for my audio probe. Normally I bypass that when testing with the volume knob, but in this photo I forgot to remove it. That makes no discernible difference in volume whether it's included or not. Let me know if we need more photos or voltage readouts!
Note that I've got a separate little perf circuit I made that provides VREF and that vref is coming into my board on the right at G1. I actually used a different power circuit there from a Wampler lesson. I've tried it with the voltage separator in the schematic, and it made no difference in volume level. It actually produced a weaker VREF around 4.2v (maybe just variance in the parts I used) so I went back to my external VREF module for convenience.
The issue is that it while it sounds right as far as I know, the volume is very low when the Vol knob is maxxed out. It's at about unity when cranked.
I built a vero board rat (I assume a similar/same circuit) and it's in an enclosure. The one in the enclosure is at Unity when the knob is at about 7:30. Turning up that vero build vol knob will get the signal really loud above unity.
I used an audio probe and noticed that on the diode side of R6 my signal is pretty quiet (same volume as when going through the vol pot when dimed) so I'm not sure if the diodes are dropping voltage too much or if there's another problem elsewhere. I've tried swapping diodes for other 1N4148s and the transistor. Currently I have a 2N5457 in there (so does the vero build) and I put a J201 in there and it's the same volume level. The opamp is a OP07.
Some voltage readings on my breadboard:
V+ 9.73v
VREF: 4.84v
IC 1: 9.68v
IC 2: 4.86v
IC 3: 4.37v
IC 4: -.2mv
IC 5: 1.7mv
IC 6: 4.83mv
IC 7: 9.75v
IC 8: 9.68v
R6: 4.82v (between R6 and C7)
FILTER pin1: .682v
Q1 D: 9.74v
Q1 S: 1.225v
Q1 G: 3.7mv
Components I've tried replacing in case they are damaged/defective:
D1
D2
C7
C10
Q1
From what I can gather on other posts, my source voltage should be about right as long as it's above 1v, so I'm just not sure what's up.
