Debug. Tonepad Small clone.

[Nolind]

Could someone please have a look at these numbers for me please.

I have built this on a tonepad pcb. I get a clean through signal with no modulation. The LM358 does not seem to be modulating. If I move the depth pot the pitch shifts whilst it is moving.

I originaly put an Electrolytic in for the 2u2 onto pin 1 lm358 but have since changed it to the closest Tant I have which is 3n3.
I have checked all the resistors.
There are a couple of small subs on the caps. A 10n in place of a 15n and a 2n2 in place of a 2n7.

Voltages are as follows.

Lm358.     1-6.67   2-4.03   3-3.72   4-0         5-0.12    6-2.05   7-0.10   8-8.88
Mn3007    1-8.27   2-8.27   3-5.78   4- 0        5-0        6- 0      7-6.77   8-6.77
cd4047     1-8.27   2-0       3- 6.24   4-8.28    5- 8.28   6-8.28  7-0        8-0       9-0   10-8.26  11-0  12- 0  13- 8.28  14- 8.28
Rc4588     1-4.5     2-4.5    3-3.58    4-0        5- 4.34   6-4.46  7-4.36    8-8.88
Q1  b-4.62 c-0 e-5.44   Q2 b-7.1  c- 8.87   e-7.37   Q3  b- 8.78  c-8.87  e- 8.28

Any help gratefully received.

Colin.

[Scruffie]

Your clock isn't working, pins 10 & 11 of the 4047 should both have about half voltage and yeah something is wrong with your 358 voltages.

Assuming you mean you used a 3u3 Tant (Not 3n3) that'll be fine, a 2u2 Electrolytic is fine there too.

Your other subs should be fine.

Check for solder bridges etc.

[Nolind]

Call off the Cavalry.

I  found a 470ohm resistor pretending to be a 470K. Only a thousand times out. It's as sweet as a nut now.

Thanks for your help!