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Doppleganger/Double Ganger 2.1d

Started by thedude99, April 11, 2015, 12:40:53 AM

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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

#1
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


thedude99

Quote from: thedude99 on April 11, 2015, 12:40:53 AM
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?
I thought this would save me money.

thedude99

Quote from: dont-tase-me-bro on April 11, 2015, 01:30:43 AM
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

#6
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

Quote from: thedude99 on April 11, 2015, 12:40:53 AM
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.
"A man is not dead while his name is still spoken."
- Terry Pratchett
My OSHpark shared projects
My website

thedude99

Quote from: alanp on April 11, 2015, 03:13:58 AM
Quote from: thedude99 on April 11, 2015, 12:40:53 AM
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

Quote from: thedude99 on April 11, 2015, 02:09:31 AM
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
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
My build docs and tutorials

thedude99

Quote from: m-Kresol on April 11, 2015, 08:18:15 AM
Quote from: thedude99 on April 11, 2015, 02:09:31 AM
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?
"A man is not dead while his name is still spoken."
- Terry Pratchett
My OSHpark shared projects
My website

thedude99

Quote from: alanp on April 11, 2015, 09:25:46 PM
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.
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
My build docs and tutorials

blearyeyes

#14
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!