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debugging fuzzy elephant

Started by ole jason, January 11, 2009, 04:50:25 PM

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ole jason

January 11, 2009, 04:50:25 PM
I've built a fuzzy elephant using the vero below (I believe it's from bean?).

*edit - not sure if I can post that here

The only change I made was using a .22uf and .01uf cap instead of the nf values.  I currently have everything wired up using test clips.  I get a bypassed signal but when I engage the switch I get complete silence, no noise or anything.

I clipped the negative end of my multimeter to the clip connected to the negative battery terminal.  Using the positive multimeter tip I checked the voltages throughout the circuit and it seems to have current everywhere.  The output point register 8.5v.  I have all 3 ground connections connected to the ground point specified on the vero layout, is that correct? 

I'm using this as a wiring guide
http://www.beavisaudio.com/techpages/StompboxWiring/StompboxWiring.gif

Anything else I should try?

bean

#1
January 11, 2009, 05:01:12 PM
I would check the pinout on your FET's as a first step.

I honestly don't remember doing a vero layout for this, but I've burned through a lot of gray matter this last year or so. It probably is my layout.  :icon_redface:

alteredsounds

#2
January 11, 2009, 05:02:57 PM
Your grounding would be fine all tied to the same point as u described.  Bean's layout does work.  Check cap polarities, transistor orientation.  If poss, always check the circuit itself works before adding all the outboard bits, i generally run the circuit into my test rig (a glorified breadboard) makes it ALOT easier to trace problems.

ole jason

#3
January 11, 2009, 05:27:51 PM
I think this is okay...


If I'm looking at the component side of the board the two electro caps should both have negative facing the top of the board?  And the two transistors should have their flat sides facing each other?

My multimeter is registering 8.5v on every solder point except the leg of C1 connected to the input (which is expected I assume).

Anything elementary I'm missing?

oskar

#4
January 11, 2009, 05:30:47 PM
It sounds as though the ground isn't getting a path back to V-

ole jason

#5
January 11, 2009, 07:37:18 PM
Quote from: oskar on January 11, 2009, 05:30:47 PM
It sounds as though the ground isn't getting a path back to V-

Could be.  I have the three wires running to the ground point on the board.
1) inner ring of the output jack
2) center ring of the input jack
3) first column, middle row lug of the switch

I then have  a wire running from the ring on the input jack to the negative battery lead.

ole jason

#6
January 14, 2009, 12:01:15 PM
Anyone have any other ideas?  Not sure what the problem is

oskar

#7
January 14, 2009, 12:04:23 PM
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