Hi, Can anyone help, I got a Muff in a trade but the sound is really weak on just over unity with everything maxed and first thought was to check for bad caps, but they all seem to look fine before desoldering and testing thought I would ask here if the voltages on the op-amps look OK?
741CN
0v (1. Offset Nul)
1.6v (2. Inverting Input)
4.8v (3. Non-Inverting input)
0v (4. V-)
0v (5. Offset Nul)
1.5v (6. Output)
9v (7. V+)
0v (8. NC)
4558N
4.5v (1.1 Out)
4.5v (2. 1In-)
4.5v (3. 1In+)
0v (4. VCC-)
4.5v (5. 2In+)
4.5v (6. 2In-)
4.5v (7. 2Out
9v (8. VCC+)
Restoring a Op-Amp Muff, help needed.
- Manfred
- Tube Twister
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What big muff type is that, Big Muff from 1977 or from 1978 ora Little Big Muff?
- plush
- Cap Cooler
Hicarboncomp1 wrote: ↑17 May 2020, 23:29
741CN
0v (1. Offset Nul)
1.6v (2. Inverting Input)
4.8v (3. Non-Inverting input)
0v (4. V-)
0v (5. Offset Nul)
1.5v (6. Output)
9v (7. V+)
0v (8. NC)
Looking at opamp muff schematics, there should be roughly 4.5-5v on both inverting, non-inverting and output pins of 741.
Check coupling caps for shortages. Or maybe 741 itself is faulty.