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Honeydripper with no sweep

Started by mcasemo, March 08, 2016, 02:02:48 AM

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mcasemo

I'm having trouble with my Honeydripper Rev 1.1.2, non-2015 version, using CA3080's.  I'm getting filtered sounds, but the envelop is not sweeping the filter.

I've reflowed and scraped solder flux and checked for bridges.  I have a USB scope and can follow a signal through IC1 and IC5.   The signal at pin 8 of IC1 is a tall squarish wave, after that it looks like a sine wave signal of similar amplitude as the input signal being inverted out of phase.  Not sure what I'm looking for.  I can see nothing on pin 5 of the CA3080's.

Maybe my substitutions are to blame?   I used a TC1044SPCA for the charge pump and connected pins 1 and 8.  I used TL074's in place of the LM324.  R21 is 2k and C2 is 1n
Pictures and voltages below, any help is appreciated, or anything specific I can look for on the scope

   IC1
Pin   TL074
1   4.95
2   5.11
3   5.06
4   16.36
5   5.12
6   5.12
7   5.12
8   2.1
9   5.11
10   5.12
11   0
12   5.1
13   5.1
14   5.05
   
   IC2
Pin   CA380
1   ignore
2   5.1
3   5.1
4   0
5   0.68
6   5.12
7   16.36
8   ignore
   
   IC3
Pin   CA380
1   ignore
2   5.1
3   5.1
4   0
5   0.663
6   5.1
7   16.36
8   ignore
   
   IC4
Pin   4558
1   5.07
2   5.12
3   5.1
4   0
5   5.1
6   5.12
7   5.11
8   16.37
   
   IC5
Pin   TL074
1   1.7
2   1.7
3   1.8
4   16.36
5   4.89
6   5.44
7   1.4
8   4.35
9   2.8
10   2.8
11   0
12   2.8
13   2.8
14   2.8
   
   IC6
Pin   TC1044SPCA
1   9.35
2   4.5
3   0
4   137 mv
5   27 mv
6   5.28
7   6.53
8   9.36




miha

I'm bumping because mine has the exact same symptoms and would to get it working :)

mcasemo