Doppleganger/Double Ganger 2.1d

[thedude99]

Project Name: Gigahearts_FX Doubel Ganger Version 2.1d

General Description of Problem: Effect works fine in dual LFO mode in both Phase and Vibrato modes.   When I click the switch to go to single LFO mode, the effect cuts out and I just have the dry signal.  LED's D4, D7,D9 & D10 turn off, as do the HFLED & LFLED.   Phase LED stays on when in phase mode.

No part substitutions.  Used the LED and LDR's recommended in the build guide.  Jumpered the pedal controls.

Steps I've taken to resolve:
Confirmed switches are good (via multimeter)
Confirmed continuity from switch lugs to PCB solder points
Triple checked switch wiring
Double checked all component values
Scraped the PCB down lightly to eliminate an solder bridges
General continuity testing to the best I could follow the schematic.  I do not get continuity from D.B2 to the negative side of D5 (I'm not sure if I should get continuity through the Diode though - should I?)  Diode measured .530V & 0V the other way.

Voltages (of DC adapter)
+ at the Jack: 9.41V
+ at the PCB 9.41V
ground at PCB 0.1mV

ICs - Left side is Dual LFO, Right side is single LFO.  Are units are V unless noted.  For the ones that fluctuate I got an approximate  upper and lower bound (meter was going to quickly to get exact numbers:

IC1
1: 4.32 / 4.34
2: 4.32 / 4.34
3: 4.32 / 4.33
4: 8.64 / 8.68
5: 3.4 - 5.54 / 3.5 - 5.5
6: 3.4 - 5.5 / 3.49 - 5.6
7: 3.4 - 5.5 / 3.55 - 5.5
8: 0.something - 7.8 / 0.something - 7.7 (couldn't get the read the lower bound)
9: 3.49 - 5.45 / 3.4 - 5.62
10: 2.9 - 6.03 / 2.9 - 6.1
11: 0.5 mV / 0.3 mV
12: 2.88 - 6.10 / 2.89 - 6.13
13: 3.18 - 5.51 / 3.12 - 5.54
14: 1.2 - 8.2 / 0 - 8.36 

Rest of the IC voltages and pictures coming in the next posts.

[thedude99]

IC2
1: 3.36-4.01 / 3.44 - 5.69
2: 3.09 - 4.95 / 3.5 - 5.57
3: 3.21 - 5.95 / 3.43 - 5.63
4: 0.4mV / 0.3mV
5: 3.7 - 5.6 / 3.61 - 5.56
6: 3.1 - 5.4 / 3.49 - 5.57
7: 3.1 - 5.9 / 3.42 - 5.63
8: 8.65 / 8.68

IC3
1: 4.06 / 4.07
2: 4.08 / 4.13
3: 4.05 / 4.13
4: 8.09 / 8.12
5: 4.05 / 4.06
6: 4.08 / 4.11
7: 4.05 / 4.06
8: 4.06 / 4.08
9: 4.12 / 4.16
10: 4.05 / 4.07
11: 0.5mV /0.3mV
12: 4.05 / 4.07
13: 4.22 / 4.38
14: 4.04 / 4.08

IC4
1: 4.05 / 4.07
2: 4.05 / 4.07
3: 3.26 / 3.28
4: 0.4mV / 0.2mV
5: 4.05 / 4.07
6: 4.1 / 4.13
7: 4.1 / 4.17
8: 8.09 / 8.12

[thedude99]

And the pictures:





Thanks!!

[thedude99]

Project Name: Gigahearts_FX Doubel Ganger Version 2.1d

General Description of Problem: Effect works fine in dual LFO mode in both Phase and Vibrato modes.   When I click the switch to go to single LFO mode, the effect cuts out and I just have the dry signal.  LED's D4, D7,D9 & D10 turn off, as do the HFLED & LFLED.   Phase LED stays on when in phase mode.

No part substitutions.  Used the LED and LDR's recommended in the build guide.  Jumpered the pedal controls.

Steps I've taken to resolve:
Confirmed switches are good (via multimeter)
Confirmed continuity from switch lugs to PCB solder points
Triple checked switch wiring
Double checked all component values
Scraped the PCB down lightly to eliminate an solder bridges
General continuity testing to the best I could follow the schematic.  I do not get continuity from D.B2 to the negative side of D5 (I'm not sure if I should get continuity through the Diode though - should I?)  Diode measured .530V & 0V the other way.

Voltages (of DC adapter)
+ at the Jack: 9.41V
+ at the PCB 9.41V
ground at PCB 0.1mV

ICs - Left value is Dual LFO reading, Right value is single LFO reading.  Are units are V unless noted.  For the ones that fluctuate I got an approximate  upper and lower bound (meter was going to quickly to get exact numbers)

IC1
1: 4.32 / 4.34
2: 4.32 / 4.34
3: 4.32 / 4.33
4: 8.64 / 8.68
5: 3.4 - 5.54 / 3.5 - 5.5
6: 3.4 - 5.5 / 3.49 - 5.6
7: 3.4 - 5.5 / 3.55 - 5.5
8: 0.something - 7.8 / 0.something - 7.7 (couldn't get the read the lower bound)
9: 3.49 - 5.45 / 3.4 - 5.62
10: 2.9 - 6.03 / 2.9 - 6.1
11: 0.5 mV / 0.3 mV
12: 2.88 - 6.10 / 2.89 - 6.13
13: 3.18 - 5.51 / 3.12 - 5.54
14: 1.2 - 8.2 / 0 - 8.36 

Rest of the IC voltages and pictures coming in the next posts.

[dont-tase-me-bro]

I'm going off memory here,cb itndoesnt the output jack have one wire to the middle Jack?

[thedude99]

I'm going off memory here,cb itndoesnt the output jack have one wire to the middle Jack?

There is a wire going from the output jack to the bypass switch. I have that in place

[thedude99]

Looking at the wiring diagram again, what is that black wire coming off the output jack sleeve?  I have the output sleeve going to ground on the PCB, and the tip going to the middle lug on the bypass switch, but nothing for that black wire where it says "Shield connect to GND at Output Sleeve".

[alanp]

General continuity testing to the best I could follow the schematic.  I do not get continuity from D.B2 to the negative side of D5 (I'm not sure if I should get continuity through the Diode though - should I?)  Diode measured .530V & 0V the other way.

I'm guessing you mean from D.B2 to the striped end of D5? Because you should.

[thedude99]

General continuity testing to the best I could follow the schematic.  I do not get continuity from D.B2 to the negative side of D5 (I'm not sure if I should get continuity through the Diode though - should I?)  Diode measured .530V & 0V the other way.

I'm guessing you mean from D.B2 to the striped end of D5? Because you should.

I have continuity from D.B2 to the striped end of D5, but not the other end of D5.

[m-Kresol]

Looking at the wiring diagram again, what is that black wire coming off the output jack sleeve?  I have the output sleeve going to ground on the PCB, and the tip going to the middle lug on the bypass switch, but nothing for that black wire where it says "Shield connect to GND at Output Sleeve".

The build doc supposes shielded wire to minimise noise. The "shield connect to gnd at output sleeve" just is for grounding the shield of the wire.
Your voltages look good to me, the LFO still seems to work, but your signal gets killed somewhere, most likely around the switch. I can't see any solder bridges and the wiring checks out. Sorry I couldn't be of more help

[thedude99]

Looking at the wiring diagram again, what is that black wire coming off the output jack sleeve?  I have the output sleeve going to ground on the PCB, and the tip going to the middle lug on the bypass switch, but nothing for that black wire where it says "Shield connect to GND at Output Sleeve".

The build doc supposes shielded wire to minimise noise. The "shield connect to gnd at output sleeve" just is for grounding the shield of the wire.
Your voltages look good to me, the LFO still seems to work, but your signal gets killed somewhere, most likely around the switch. I can't see any solder bridges and the wiring checks out. Sorry I couldn't be of more help

This actually is quite helpful.

I am suspecting the problem is somewhere along the D.A1 path.  The switch connects D.A1 to D.A3 & D.B2 to D.B3 for dual.  I assume all 4 of those paths are fine since dual mode works.  For the single mode, D.B2 isn't connected to anything, and D.A2 is connected to D.A1.  By process of elimination that leaves D.A1 (unless I am totally misunderstanding the circuit)

I think I need to work back from the switch to the problem on the D.A1 path.  Should I be doing that with continuity, voltage test or an audio probe? (or something else).

[alanp]

Have you checked continuity across the switch lugs?

[thedude99]

Have you checked continuity across the switch lugs?

Yes. Continuity across the switch lugs is fine.

[m-Kresol]

Audio probe is definitely a good idea. Just work around that area of the schematic and see where your signal is lost. Once you find the part in question you can reflow the joints there, check the value and look for solder bridges etc.

[blearyeyes]

Sounds like one of the "dual" connections is getting shorted or to the wrong place somehow.  That would kill the LEDs and stop the effect.  Dual.B2 BY.B1   Dual.B3 connects to a trace that runs to all of the LEDs you say cut out.  Find those three labels on the schematic and start there.  Right below LDR7

Audio is getting all the way through the circuit in dual mode so start with the LEDs losing power.

If you separate the schematic into audio, modulation control  and led voltage while you look at it, it helps.

Good luck!