Hey guys-
I see the Bass Chorus is a popular one for having issues; mine is no exception. I've breadboarded it, and it's very close to working. I just don't have an oscillator. I have a nice strong bass signal at the output. The blend works fine- nasal "effect" signal at one end of the pot, and the strong bass signal at the the other end. I can get a slight chorus going if I manipulate the rate pot, but just for a few milliseconds. The effect is "there," it just won't wind up on its own. The LED doesn't light up, unless I short pins 3 & 4 on IC3; then it will light and latch, but no oscillation. I've been screwing with this thing for weeks, taking it apart, rebuilding it, checking parts, changing out parts- I'm just not seeing a clear source of the issue. Could someone more knowledgeable take a look at this and give me a couple tips to chase down, please? Below are my voltages. Thanks.
Bench power supply reads 9.23V, 45 mA
Power section outputs: +V= 8.51 +9V= 9.23 Vb= 8.38 1/2 Vb= 4.63
IC1: 1- 4.63 5- 4.63 2- 4.63 6- 4.63 3- 4.63 7- 4.63 4- 0.00 8- 8.52
IC2: 1- 0.00 5- 8.38 2- 4.17 6- 4.17 3- 5.92 7- 7.52 4- 7.82 8- 7.52
IC3: 1- 7.80 5- 4.26 2- 4.30 6- 4.27 3- 7.71 7- 7.77 4- 0.00 6- 8.51
IC4: 1- 8.37 5- 0.09 2- 4.17 6- 8.26 3- 0.00 7- 2.68 4- 4.17 8- 7.82
Q1: E- 2.85 B- 3.26 C- 8.52 Q2: E- 3.84 B- 4.38 C- 3.84 Q3: E- 3.26 B- 3.76 C- 8.52 Q4: E- 5.71 B- 5.71 C- 8.51 Q5: E- 3.33 B- 3.86 C- 8.51 Q6: E- 0.00 B- .08 C- 8.15
D1: A- 2.67 K- 8.15 D2: A- 1.60 K- 2.67 D3: A- 5.70 K- 3.11 D4: A- 9.23 K- 8.51
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