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Dead Circuits

6/8/1999 12:41 PM
Dead Circuits
You're probly all getting sick of my stupid beginner questions but here goes another one! :)  
In the last 2 weeks i have built  
1.Electra Distortion - working  
2.Swell device - working(somewhat)  
3.Roger Mayer CLassic Fuzz - DEAD Circuit (replaced some parts w/ similar ones)  
4.DOD envelope filter 440 - DEAD circuit  
5.4 transistor electra distortion mod - DEAD circuit  
I don't understand it.......i know for #'s 4 and 5 i have all of the caps,resistors and diodes connected right...i have checked them an uncountable # of times (other people too), but they are still dead. I followed the schematics exactly but, even layed everything out as shown on the schematic.......  
Most of the above pedals required some +/- caps, but i used non-polarized.  
Also i have tested the 9v w/ my tongue :) still some kick left in it.  
Anybody have any ideas?
6/8/1999 12:50 PM

Yes, I have some ideas.  
Please check out:  
These techniques will probably get your circuits working.  
While you are there, check out:  
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6/8/1999 2:06 PM

One of those little quips I've picked up over the years is that Mother Nature waits for you at the end of the assembly line - which means that no matter what someone thinks they're doing, the laws of physics still apply when you try to run something.  
As a beginner, you are at the hardest part of the slope. Nothing in particular about electronics makes any sense to us in our everyday experience, and even the smallest mistake in connections, component value, and goodness or badness of a component may make something not work.  
I can tell you that I have personally built the Electra Distortion, swell device (which, as I noted, is not a true swell device at all), and many variants of the fuzz face, of which the RMCF is one, and they all worked.  
It's not possible for us to tell you what is wrong from such a distance with no more information than you have there.  
In the step-by-step debugging procedure I typed in I noted that it is very important to know the proper DC levels inside a circuit. Almost all totally-dead circuits can be debugged to at least partially working by studying the DC voltages. For us to help, you're going to have to use a voltmeter to read the voltages at the pertinent places in the circuit. Since you're testing batteries with your tongue, I suspect that you may not be using a meter at all.  
If you're going to build effects, get one or get access to one and learn to use it. That may be the key in letting us be able to help you.  
By the way, three dead, one working, and one semi-working in your first two weeks is not a bad start.
6/8/1999 2:27 PM

Yes i have a meter, which measures ac,dc,resistance among other things, but i am currently learning to effeciently use it, i have tested those curcuits for dc power and the places where there is no power thw wires are hooked up correctly...also i am getting very little power in most other places (other than the direct + battery connection) would a fresh battery remedy this?  
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