madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: blearyeyes on July 18, 2014, 04:28:38 AM

Title: Lace's Alan's DoubelGanger Help needed SOLVED!
Post by: blearyeyes on July 18, 2014, 04:28:38 AM
 :-[  Docs w/ Schematic.  :-[
https://dl.dropboxusercontent.com/u/24630132/Gigahearts_FX_DoubelGanger_2.1d_BuildGuide%20v4.pdf (https://dl.dropboxusercontent.com/u/24630132/Gigahearts_FX_DoubelGanger_2.1d_BuildGuide%20v4.pdf)

Passes audio without effect.
Antiphase switch stops all LED activity when in Single Oscillator Mode

IC#1
1-  4.2v
2- 4.2v
3- 4.2v
4- 8.84v
5- OSC*
6- OSC
7- OSC
8- OSC
9- OSC
10- OSC
11- 2Mv
12- OSC
13- OSC
14- OSC

*OSC= SWITCHING BETWEEN VOLTAGES

IC#2
1- OSC
2- 4.2 - 4.6v
3- 4.2v
4- 4Mv
5- 8.42v
6- OSC
7- OSC
8- OSC

IC#3
1- 4.3v
2- 4.3v
3- 4.3v
4- 7.83v
5- 4.3v
6- 4.3v
7- 4.3v
8- 8v

IC#4
1- 4.3v
2- 4.3v
3- 3.4v
4- 0
5- 3.4v
6- 4.3v
7- 4.2v
8- 7.9v

Any help is greatly appreciated.
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 18, 2014, 11:01:01 PM
Phase LED pads are backwards?

Looks like the square pad is the cathode...

It helps if you solder the bypass switch with the terminals oriented the correct way...sheesh.

So far I have the Phase LED working and getting signal through the board to the outputs but no effect.
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: alanp on July 18, 2014, 11:22:33 PM
IC4 should be the main audio op-amp. 4A is the input opamp, 4B is the output opamp.

IC3 is the filter op-amp.

IC2 does buffering/whatnot for the LFO signal.

IC1 is the LFO op-amp.

Are the LEDs in the LED/LDR combo's working, as in being driven by the LFO in either triangle or square waveforms?
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 19, 2014, 04:16:38 AM
Yes all the LEDs are working. I think I have a bad chip socket under IC3. I got the effect to work after applying a little pressure to the chip. It was intermittent. Pulled the chip and it looks like someone was having a bad day in china. After first pass at un-soldering the socket I found a hair, the effect started working but I must have something wired wrong as the lows were working while the effect was on, then in bypass, the highs were working even though the indicator leds went off..  so I re-soldered the socket and now it isn't working at all again,  but I know where to start tomorrow, I think.. well as much as I ever know.
Time for a beer.

Oh, the only other weirdness is when the dual switch is off the Antiphase switch kills all the LED activity.

Alan, thanks for the info it helps.




Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 19, 2014, 07:12:12 AM
OK, I have half of the flanger working while in bypass and what has me wondering is after wiring up the bypass per the diagram, I am getting the main leds lighting while the indicator leds are dark, and the indicator leds lighting when the switch is in bypass...  There are just two wires connecting together to turn on the pedal and both sets of leds are on the same circuit?
One output is the direct output and the other is the effect.. What am I missing?

Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: alanp on July 19, 2014, 07:24:18 AM
... think I'm going to have to ask for photos.

The bypass switch uses two poles -- the first pole selects between dry and phase, the second turns on the LEDs (all of 'em except the phase/vib) by connecting their grounds.
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 20, 2014, 05:56:12 AM
I'll shoot pics tomorrow when I get back in town..

Thanks for helping I really appreciate it..
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 21, 2014, 02:28:28 AM
here is a link to the bypass switch wiring:

https://www.dropbox.com/s/fqe75f4naz5ethm/2014-07-20%2018.25.30.jpg

Double LFO switch:

https://dl.dropboxusercontent.com/u/24630132/IMG_0301.JPG

Phase Switch:

https://www.dropbox.com/s/eify5fettlgk4b4/IMG_0294.JPG%20%282%29.JPG
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 21, 2014, 03:01:55 AM
I personally think there isn't anyway for these LEDs to be lighting up opposite while being switched with a two lead switch unless there is a short somewhere in the LEDs circuit. Does that make sense?
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: the3secondrule on July 21, 2014, 04:45:31 AM
It looks like your bypass switch is wired significantly different to the wiring diagram?
I only see 4 wires on your bypass switch, there's 6 on the wiring diagram

or am i missing something
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: alanp on July 21, 2014, 05:01:13 AM
Is your pha.a2 connection going to the ground pad?

QuoteI am getting the main leds lighting while the indicator leds are dark, and the indicator leds lighting when the switch is in bypass...

This is what really has me confused -- not sure how it's possible to manage that one!
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 21, 2014, 05:29:05 AM
Quote from: the3secondrule on July 21, 2014, 04:45:31 AM
It looks like your bypass switch is wired significantly different to the wiring diagram?
I only see 4 wires on your bypass switch, there's 6 on the wiring diagram

or am i missing something

There are 5 posts and one is coming from the Phase/Vibe switch to ground. I just ran it to ground on the board...  ISSUE?
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 21, 2014, 05:34:58 AM
Quote from: alanp on July 21, 2014, 05:01:13 AM
Is your pha.a2 connection going to the ground pad?

QuoteI am getting the main leds lighting while the indicator leds are dark, and the indicator leds lighting when the switch is in bypass...

This is what really has me confused -- not sure how it's possible to manage that one!

I know as I look at the schematic there must some partial ground or.. I'm dumbfounded to be sure....  I was going to post a movie so you wouldn't think me mad!
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: LaceSensor on July 21, 2014, 07:38:23 AM
ignore me, looked at photos wrong

can you post full board photos of both sides of the PCB please?

assuming you are checking the output from Lug 2 of the bypass footswitch? there is no wire soldered there...
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 21, 2014, 07:31:41 PM
Yes, while testing, I have a clip that runs to my test amp hooked up to post #8 on the switch which sends output from bypass or effect, but just not when I photographed it.   I also made sure that #1 and #2 posts were closed (to ground) when the effect output was selected to light the LEDs.

I have inspected the soldering with magnification but would love another set of eyes. (mine are a little Bleary)

I have had this pedal do a lot of very confusing things. At one point I was getting the High end flange while engaged and the low end flange while in bypass.

There is an issue with IC3. At first I was only getting clean signal from both bypass and EFX output. That led me to IC3 not functioning. I pressed gently down on the IC and got Effect. Which led me to pull the chip and inspect the socket. Some holes in the machined socket are twice as big as others leading me to believe it is bad. I have been unable to remove the socket even after de-soldering it is fairly well stuck and I don't want to pull on it. I'm going to cut it and pull one pin at a time to not damage the board. Another idea is perhaps traces that run under IC3 or close to IC3s pins somehow are shorting.  This IC and socket when soldered completely in stops the effect from working, after sucking out most of the solder the effect works in various strange ways.  I have tried several different TL074 ICs.

I'll try to get good pictures of the circuit board top and bottom tonight when I get home.

Thanks you guy for your help. I really appreciate you taking the time to help.
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: LaceSensor on July 21, 2014, 10:38:11 PM
just get some decent snippers and cut each leg of the ic socket, then suck out the solder and bit of "leg" that is left

Its clearly an issue with the build that you need to address before anything else can move on....

The reason I ask for full board pics is to check values etc.
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 22, 2014, 05:25:29 AM
https://www.dropbox.com/s/9i9o0zwmrmns501/2014-07-20%2018.28.59.jpg

https://www.dropbox.com/s/obxfsjxvclgy55e/2014-07-21%2021.14.56.jpg
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 22, 2014, 05:32:55 AM
do these boards have through PCB pads?
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: LaceSensor on July 22, 2014, 07:16:51 AM
Yes, they are standard 2 side through hole plated...

you have got the pedal controls hooked up properly, or at least jumpered the pads, right?
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: LaceSensor on July 22, 2014, 10:08:06 AM
not had time to look at resistors but the cap values and orientations seem legit
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 22, 2014, 07:04:47 PM
I'll go through the values.

What could possibly get power to the indicator LEDs and have them blinking (although seemingly dimly) when the bypass switch is lifting the ground to the circuit.  Must be getting shorted to ground somewhere in that circuit...

I'm going to write down all the pieces to this puzzle and post them in one place.

Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: LaceSensor on July 22, 2014, 07:36:34 PM
Short, solder bridge, who knows.

The pcb was triple verified... So sorry to say it's an error your end dude  :-[
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 22, 2014, 08:16:58 PM
Ian, I totally agree. Like for instance, having the indicator LEDs in backwards?
I would say that qualifies as a pretty stupid error on my end... :-[

I replaced the IC3 socket, which I think started this whole ordeal..
Nothing like pedal building to keep you humble.
Sheesh.

Thanks again for all your help guys...
Dan
Title: Re: Lace's Alan's DoubelGanger Help needed
Post by: blearyeyes on July 22, 2014, 09:57:58 PM
Quote from: alanp on July 21, 2014, 05:01:13 AM
Is your pha.a2 connection going to the ground pad?

QuoteI am getting the main leds lighting while the indicator leds are dark, and the indicator leds lighting when the switch is in bypass...

This is what really has me confused -- not sure how it's possible to manage that one!

Well if you wire the indicator LEDs in backwards.
Title: Re: Lace's Alan's DoubelGanger Help needed SOLVED!
Post by: LaceSensor on July 22, 2014, 10:29:44 PM
Good news. So does it sound good then?!
Title: Re: Lace's Alan's DoubelGanger Help needed SOLVED!
Post by: blearyeyes on July 22, 2014, 10:50:56 PM
Yes It sounds awesome!
I am getting the hang of the controls. 
Very cool pedal.
Nothing else like it really.

This is a definite must build!