Madbean Dig dug help (like seek wah/vanishing point)

Started by MikeH, April 04, 2012, 08:11:25 PM

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MikeH

Ok, so I'm trying to build one of these:

http://madbeanpedals.com/projects/DigDug/docs/DigDug.pdf

And I've run into a wall.  I'm pretty good at debugging my builds these days, but this one is a new animal to me and it's giving me fits.  

Here's what it's doing:

It does not sequence- all of the LEDs flash at the same time.  Speed controls work.  Random mode causes all LEDs to blink randomly, but at the same time.  The shut off switch stops the blinking.

So I would guess the problem lies in the 4039 schmitt trigger area - I have triple checked every component value and wired connection as well as every trace for bad solders or shorts and I have found nada.  I have also looked up and double checked the pinouts on the transistors/FETS.  I have swapped the 4093 for a different one.  I do not have another 4017 to try.  

Before the voltages, what should I see at the 4093 pin 3/4017 pin 14 junction?  It seems like there should be some action going down there, and I'm seeing very little voltage "changing hands".

The Voltages on the 4093 are almost all oscillating, but here they are (I'm just going to post voltages for the sequencer):

CD4093:
1= 9.3v (with small fluctuations)
2= 9.3v (also with small ~)
3= 0.60 - 0.65v
4= 9.31 - 9.42v
5= 9.49 - 9.51v
6= 1.41 - 1.57v
7= 0.0v
8= 0.0 - 9.61v
9=0.0 - 9.61v
10=0.0 - 9.61v
11= 0.0 - 9.61v
12= 4.8v
13= 4.8v
14= 9.61v

Q2 BS170
D= 4.83v
G= -3.1v (9.6 w/ sw1 closed)
S= 4.84v

Q3 BS170
D= 9.6v
G= 9.4 (0.0 w/ sw2 closed)
S= 9.42v

(Both of these look screwy to me, but the switching controls work, and they don't look any better if I change their orientation - I guess they are not being used in a typical 'amplification' scenario and I just don't understand how they are being used)

C= 9.0v (with small ~)
B= 1.5 - 4.9v
E= 9.31v

(This too looks screwy - is this being used to make the "random" function work?)

CD4017
Pins 1-7= 0.01 - 2.22 fluctuating
8=0.0v
9=0.0v
10=0.0-1.5v
11=0.0v
12=3.13 - 8.68v
13=0.0v
14=0.60 - 0.65v
15=0.0v
16=9.6v

D1
c= 0.0v
a= -0.5v

D2
c= 0.0v
a= 0.0v (I've got a good feeling about that one!)

D3
c= 4.48v
a= 1.7v

D4
c= 0.0v
a= -0.44v


Ok... phew.  That took a long time to type out.  Hopefully someone here can help me out...  Any help is appreciated, thanks in advance!
"Sounds like a Fab Metal to me." -DougH

MikeH

"Sounds like a Fab Metal to me." -DougH

MikeH

Hrrrmmmm... no takers?

Sorry for all of the bumping- I know this is a pretty obscure pedal; I imagine not a lot of people have built it.  If anyone has one they can take voltages on, that would be awesome.
"Sounds like a Fab Metal to me." -DougH

Morocotopo

Hope you get it right Mike. I can´t help you but I wish you success, I´m currently breadboarding a CD4049/CD4022 sequenced wah, but the control part is the Vanishing Point, not the Dig Dug one.
Morocotopo

MikeH

"Sounds like a Fab Metal to me." -DougH

Morocotopo

Mike, I only looked at the Dig Dug schem lightly, but I think the clock oscillator is different, it's done with an opamp, while the Vanishing Point is all 4093, no opamp, so...
Morocotopo

MikeH

I see... Well, the 4017 is being triggered or controlled by voltage on the 'clock' pin which would be pin 14.  Can you tell me what sort of voltages your 4017 is seeing at that pin?  It would help me isolate the problem.
"Sounds like a Fab Metal to me." -DougH