Brown Betty

LanePw

New member
I'm having an issue with no sound when the effect is engaged. The indicator led works as should and I've got sound in bypass. Only L3 inside is lighting up dimly. I double checked the LED orientation on the rest and they're correct and worked on my breadboard after removing to check them.
I'm getting almost 6v on one side and 3v on the other of the one that's working and none on the others. All IC's are getting power. Kind of stumped on this.
 

LanePw

New member
Can you Test these matching Colour circles for Continuity:

View attachment 7848
All of those check out. I flipped L4 around making L3-4 symmetrical and now both light up. L2 pad K on component side has now pulled off when I removed to try the same thing I did on the presence circuit. I've got continuity from C6 to anode on L2. Jumped L2 A to L1 K to make the circuit whole again and still no lights on either L1 or L2 even with the gain pot rolled all three way up or down. IC 2 is sill sending to C6 and C6 to L2, but nothing.
 

LanePw

New member
I fixed the pad on L2. Everything in the gain circuit is passing signal.
All IC's are operating as they should. I'm at a complete loss on this one. I tested every component before installing even.
I'm totally baffled at this point
 

music6000

Well-known member
Can test for Continuity on the Matching colours & supply Voltages for each TL072 :
I'm not a Fan of those Op Amp Sockets!
Use Machined Pin type Only!
Brown Betty LED Continuity Check.jpg
 

LanePw

New member
Can test for Continuity on the Matching colours & supply Voltages for each TL072 :
I'm not a Fan of those Op Amp Sockets!
Use Machined Pin type Only!
View attachment 7865
Curious thing happened when I was checking those pink and yellow circled pads. I had a probe on the pink on the gain pot and checked at C6 which is in-between the branches of that circuit, the LED's would come on. Bad pot maybe?
 

music6000

Well-known member
So, you still have continuity from Gain 3 to both LED's but not from L2 to C6 BUT Continuity from Ic Pin 7 to C6?
 

music6000

Well-known member
Just to clarify, Those 2 - 47pF are really Large!
Can tell me what is written on them, ie 47, 471, 472, 473, 474.
 

LanePw

New member
Just to clarify, Those 2 - 47pF are really Large!
Can tell me what is written on them, ie 47, 471, 472, 473, 474.
Marked 470. I have replaced C6 with another. It tested 44pf. The one in the pic is another from the same batch.
 

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LanePw

New member
I have also now jumped L2 to C6 and have continuity.
Volume pot A50k is very scratchy I just noticed.
 

music6000

Well-known member
Are you getting sound from the pedal now?
Spray the A50K Volume pot only with Electrical Cleaner if you have some.
 
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