problems with my wiring

Started by mrfjones, January 25, 2005, 11:11:54 PM

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mrfjones

I am working on a couple different pedals, i am new to this and i really don't understand what all i am doing, or in this case doing wrong.  first i tried making a "bazz fuzz".  i added two germanium diodes in the place of the silicon. when i tested the circuit it read that i was getting good voltage throughout the circuit, but with the transistor in place, i got no sound.  i took the output and moved it from the collector to the base and bypassed the transistor (it is socketed and out at this point)  i got to hear the sound of the guitar distorted but not amplified at all.  What could i have been doing wrong.  my circuit even looks like the schematic, except for the other diode.  my solder joints are good and strong, i took the socket out and tried wiring the transistor straight to the circuit. but i still get nothing.  I get no output at all when switched on.  what can i test or what can i try?  I am having the same issue with a rangemaster clone

MartyMart

That sounds like a "pinout" problem to me, I've had similar problems..... so you need to search the forum for "pinout" or the number on your transistor/download the data sheet for your transistor, from the manufacturer... yes they are often different !
It's a bummer, but that will prevent the circuit from working at all.
Your Ge diode subs will work, but will cause the circuit to "clip" sooner but it should sound a bit "sweeter" with Ge, make sure you have the "cathode/anode" the right way around too.
Cheers,
Marty. 8)
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

petemoore

I used to measure every resistor and count connections at every node while populating a board. This lowered build/debug time.
 While debugging...
 I set the DMM for resistances or continuity, and calculate each [in cct] resistance reading for 'offness' [whether I suspect a bad value ..or broken resistor, rare I remember having found 2 such], or pulling one end of a resistor from the board to measure only it's value.
 Then I'd check that the R leads Actually had continuity where they were supposed to, and nowhere else.
 Beep mode, I check all ground points. then test adjacent socket lugs for non-continuity, rarely do I make adjacent socket lugs connected.
 Those Bazz's when I built them, Didn't really benefit so much from my excellent debugging  :oops:  techniques [voltages/A. probing didn't direct me to problems] as much as just relooking it over..then finding the 'item' preventing the cct's function.
 Usually it's one of the many things mentioned on the debugging page.
Convention creates following, following creates convention.

mrfjones

after really looking at all this stuff i got to wondering, since it is a npn transistor, should i really be putting positive +9v into a negetively polar lug and then on the other side having neg and neg meet?  i hope i make sense.  it just seems to me that the lugs should got c=n b=p e=n  but then i don't understand why i would be using pos. on one of the n lugs and neg on the other.  it may sound dumb but i have been looking over everything trying to get this pedal to work for over a week and i can't seem to find out what is going on.  

oh and i did look up the pin out and data sheet on the transistor and it said the same thing as the back of the package.

petemoore

For most reliable reference, Find a good schematic, follow it.
 NPN Neg. gnd.
 pos battery lead goes to the 'top'
 Negative ground
 For general reference, the + of the polarized caps always goes toward the most + side of the ciruict.
  Gnd. is indicated by some kind of - often parallel to the length of the cap, the lead nearest the - sign on the cap goes to gnd.
 If you're using non-polarized caps, either way around is the same.
Convention creates following, following creates convention.