[SOLVED] Dirtbag v3205 - No clock signal?

[eldanko]

Howdy friends -

Finishing up a v3205 Dirtbag build and having a small problem.  I'm getting signal to pin 7 of IC4, but no delay on pin 3 or 4 - just noise/AM radio/etc.  I'm also not getting noise on pins 2 or 6 - these are from the clock, right?  I've swapped IC9 out and no change.  Thoughts?

I can post voltages later, didn't have time to record on my lunch break...

[Scruffie]

Voltages will be key here. I'll take a glance when you post them.

The 4047 should have roughly half supply on pins 10 & 11 though, this should reach pins 2 & 6 on both V3205s.

[eldanko]

As always, thanks for your help Scruffie... and thanks for helping save my last 3005 build as well 

Input: 9.1

IC1
1) 4.5
2) 4.5
3) 4.5
4) 0
5) 4.4
6) 4.5
7) 4.5
8 ) 9.0

IC2
1) 1.0
2) 1.7
3) 1.7
4) 0
5) 1.7
6) 1.7
7) 7.6
8 ) 1.7
9) 1.7
10) 6.5
11) 4.4
12) 1.7
13) 9.1
14) 1.7
15) 1.7
16) 0

IC3
1) 4.5
2) 4.5
3) 4.5
4) 0
5) 4.5
6) 4.5
7) 4.5
8 ) 9.1

IC4
1) 0
2) 9.1
3) 3.9
4) 4.0
5) 8.2
6) 0
7) 4.2
8 ) 8.0

IC5
1) 0
2) 9.1
3) 4.0
4) 4.1
5) 8.2
6) 0
7) 4.7
8 ) 8.0

IC6
1) 4.7
2) 4.7
3) 4.7
4) 0
5) 5.1
6) 5.1
7) 5.1
8 ) 9.1

IC7
1) Varies
2) 4.8
3) Varies
4) 0
5) 4.8
6) 4.8
7) Varies
8 ) 9.1

IC8
1) 4.5
2) 4.5
3) 4.5
4) 0
5) 6.5
6) 6.5
7) 6.6
8 ) 9.1

IC9
1) 0
2) 8.8
3) 0
4) 9.1
5) 9.0
6) 9.0
7) 0
8 ) 0
9) 0
10) 9.0
11) 0
12) 0
13) 0
14) 9.0

Ok, judging by what you said about pins 10 and 11... there's definitely a problem there.

[Scruffie]

As always, thanks for your help Scruffie... and thanks for helping save my last 3005 build as well 

Ok, judging by what you said about pins 10 and 11... there's definitely a problem there.

Did I? Haha, no worries for whatever I did then!

Yup... check round there and try a different chip, CMOS is static sensitive.

[eldanko]

Swapped in a known good 4047, still no dice.  I also cannot find any soldering errors or bad part values in that vicinity for the life of me.  Any specific parts I need to check?  Could a bad v3205 cause this?

[Scruffie]

Swapped in a known good 4047, still no dice.  I also cannot find any soldering errors or bad part values in that vicinity for the life of me.  Any specific parts I need to check?  Could a bad v3205 cause this?

Take 'em out and see if they're dragging that voltage down, could be something round there.

[eldanko]

With the 3205s out, I get 9.5 on pin10 and 0 on pin11.  With them in, I get 0 on pin10 and 9.5 on pin11.

[eldanko]

Got it!

Wonky v3205 to blame.  Got it biased up nice now.  Still getting a decent whine with the delay knob cranked - that's normal, right?  Other than that, sounding great.

Thanks again for the debugging help.