M51134 Octaver not working

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M51134 Octaver not working

krsdrm
So I built the M51134 octaver from Alex's layout and I'm not getting signal to the output. I took voltages which post as well and I tried to follow the signal with an audio prob and I have signal to all the chips but it is weakest at pin one of ic 1 which is the one closest to where the power comes in but I don't really know what that means. I'm also getting sub octave noises coming from pin 18 and 19 but it's fairly quiet and barely effected by the signal. I've looked over the circuit a hundred times and I can't figure out where I went wrong so I give up hopefully someone will see something I'm missing. Thanks

IC 1
1 2.381
2 2.381
3 2.60
4 .000
5 2.381
6 2.383
7 2.390
8 5.834

IC 2
1 2.689
2 2.632
3 2.619
4 .001
5 2.619
6 2.611
7 2.583
8 5.832

IC 3
1 2.696
2 .001
3 2.059
4 4.750
5 4.752
6 3.013
7 3.017
8 3.018
9 8.22
10 7.47
11 3.037
12 .001
13 3.023
14 3.032
15 3.032
16 3.033
17 2.128
18 3.106
19 3.030
20 2.866


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Re: M51134 Octaver not working

Alex
That's not a stripboard (vero). You've used a perfboard. The points are not connected.
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Re: M51134 Octaver not working

Hozy31
I think that is stripboard if you look closely. You can see that the stripcuts are a different colour to the solder masked copper. Must admit i've never seen that type before, bet its expensive.
"Red velvet lines the black box"
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Re: M51134 Octaver not working

Hozy31
Looks like you have missed a resistor next to the diode. Everything else looks good.
"Red velvet lines the black box"
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Re: M51134 Octaver not working

krsdrm
It is strip board it's just that its printed over in the gaps. I didn't put the clr in because I planned on using an optical bypass board when I boxed it up and the bypass led will be on there. I was wondering if that might be a problem since it does go to ground.
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Re: M51134 Octaver not working

Hozy31
No, that's not the problem. I didn't realise it was the CLR until you mentioned it, sorry. The only other thing i noticed is your jumper with two double links looks dodgy in the picture, but i can't really see it clearly so it may be ok.
"Red velvet lines the black box"
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Re: M51134 Octaver not working

Alex
This post was updated on .
Ops! Rushed post! There would be no voltages otherwise!
The voltage on pin 9 of the M51134 seems correct but those on pins 8 of IC1 and 2 are way too low.
Have you tried reflowing the solder? Change the 5532s? Run a knife between all the rows? If you've already done that, can you try to jump the 100R resistor going from D1 to IC1 pin 8?
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Re: M51134 Octaver not working

krsdrm
I've re-flowed several spots that I thought looked questionable and tried to go through and scrape between all the adjoining spots on the board but I'll re-flow both the ic's and swap out the 100R. Thanks
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Re: M51134 Octaver not working

krsdrm
In reply to this post by krsdrm
So I took out the 100r and replaced it with a jumper and the voltages on the 5532's pin 8 jumped to 6.3ish. Still no output. I went back with the audio probe and found I was getting signal all the way to the 220nf connected to the output but not on the end that connects to the output. So I moved the output to the other end of the 220nf and I was getting some output and a very subtle octave effect with a quiet hissing or scratchy noise. If I adjusted the pot some places were cleaner sounding but the signal was definitely below unity. I also noticed that the effect sounded more like it was 70-80% dry signal to 20-30% octave and you could really only hear the effect on the low E string. Anymore ideas? Should I get all the voltages again?