No effect from Analog Vibrato Rev. 2.0

[Zoot]

Hi guys,

I just finished an Analog Vibrato that won't do anything as an effect. It does work on by pass though.
I have no much clue about what is going on, I've built some simpler pedals, they worked.
Maybe I have short?

In any case, I would really appreciate some guidance in how to debug this thing, I went through some debugging tutorials, I'm learning a lot, but still not there.

Thank you very much in advance!
Zoot

I'm Sharing voltages and pictures below:

Adaptor voltage = 9.41v, no battery used

Q1 (3094, npn EBC pinout)
E = 1.80
B = 2.25
C = 9.41

Q2 (3094, npn EBC pinout)
E = 2.57
B = 3.15
C = 9.41

Q3 (3094, npn EBC pinout)
E = 2.22
B = 2.74
C = 9.41

Q4 (3094, npn EBC pinout)
E = 1.64
B = 2.22
C = 9.41

Q5 (3094, npn EBC pinout)
E = 4.75
B = 4.88
C = 6.90

Q6 (3094, npn EBC pinout)
E = 3.60
B = 4.06
C = 8.56

Q7 (3094, npn EBC pinout)
E = 0
B = 348 mV 0,3
C = 7.33

Q8 (3096, pnp EBC pinout)
E = 9.41
B = 8.82
C = 1.21

Q9 (3096, pnp EBC pinout)
E = 9.41
B = 8.82
C = 8.82

Q10 (3094, npn EBC pinout)
E = 0
B = 0.59
C = 8.82

Q11 (3094, npn EBC pinout)
E = 0
B = 0.59
C = 0.59

Q12 (3094, npn EBC pinout)
E = 8.22
B = 8.58
C = 9.41

Q13 (3096, pnp EBC pinout)
E = 9.41
B = 8.78
C = 9.38

Q14 (3094, npn EBC pinout)
E = 9.41
B = 9.22
C = 8.56

IC1 (4558)
P 1 = 3.28
P 2 = 3.18
P 3 = 3.18
P 4 = 0
P 5 = 3.18
P 6 = 3.18
P 7 = 3.18
P 8 = 9.41

IC2 (3207)
P 1 = 8.55
P 2 = 4.13
P 3 = 4.54
P 4 = 4.54
P 5 = 0
P 6 = 4.15
P 7 = 2.56
P 8 = 7.99

IC3 (3102)
P 1 = 8.56
P 2 = 4.13
P 3 = 0
P 4 = 4.15
P 5 = 289mV
P 6 = 8.21
P 7 = 3.45
P 8 = 7.99

IC4 (TL022)
P 1 = 4.75
P 2 = 4.75
P 3 = 4.73
P 4 = 0
P 5 = 4.54
P 6 = 4.61
P 7 = 4.71
P 8 = 9.41

IC5 (BA6110)
P 1 = 4.74
P 2 = 4.74
P 3 = 188mV
P 4 = 1.22
P 5 = 0
P 6 = 4.8
P 7 = 4.8
P 8 = 4.81
P 9 = 9.41

[Mark Hammer]

Aye chihuahua, that's one big circuit to troubleshoot!  I gather it is a clone of the VB-2.
The voltage on pin 3 of the 3207 (essentially half of V+) seems wrong.  BBDs have to be biased in order to pass signal, by adjustment of that trimmer in the lower right hand corner, labelled "bias".  You'll have to experiment with its setting.  Note that you will not damage the chip by doing so.  Adjusting it will pass through a zone where you can hear some delay but it is distorted, through to a zone where the delay signal gets louder and cleaner, and finally back through a zone where it gets quiter and distorted again to finally no delay signal.  You're looking for "the sweet spot".

[Scruffie]

I'd say the more pressing matter with the 3207 is the wildly different output pin voltages. The joint on pin 8 in your photos does look a bit poor.

That and a lack of any moving voltages from the LFO.

[Zoot]

Mark and Scruffie,
Thank you both for the answers.
Today I took your recommendations and applied both, reheated some of the mentioned joints, and biased with the trim.
Pedal works now perfectly, all its functions. And it's a great pedal.
Cheers to you. Great help, on the spot.
Best regards,
Zoot

[Mark Hammer]

Excellent!  Every little bit of good news these days is a ray of sunshine.