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.
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
And the pictures:
(http://i.imgur.com/4Ah8eiv.jpg)
(http://i.imgur.com/2vU6YDi.jpg)
(http://i.imgur.com/JbFYFPK.jpg)
Thanks!!
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.
I'm going off memory here,cb itndoesnt the output jack have one wire to the middle Jack?
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
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".
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.
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.
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
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).
Have you checked continuity across the switch lugs?
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.
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.
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!
I found the problem. The square pad on D10 has lifted on the solder side of the board and is not getting a connection. I touched a piece of wire between that solder point and the non-striped side of D6 (how they are connected in the circuit) and it came to life.
I can put a jumper between the two to get it to work - but is there a better way to fix this?
Thanks to everyone here for the help - it is much appreciated.
If you have a look at page 5 of the build doc, you can see that the square pad of D10 is connected to D.B3 and D6 (there are no further connection on the top layer of the board). If the pad has indeed completely lifted, you'll need to reconnect it to both. I'd suggest small jumper wires on the solder side of the board. No one will see it.
I noticed that other path as well - but the jumper between D6 and D10 was all it took. Must either be a partial lift or some other issue as that path is fine.
Either way - I now have a fully functional Doppleganger. Thanks to all for the assitence. It is very much appreciated
I really enjoyed that build. Cool pedal.