Well, now that you've pointed it out, shouldn't that 56K resistor be connected between the 0.0033uF cap & the volume pot's lug 1 to ground in the first schematic?
jrod wrote:Well, now that you've pointed it out, shouldn't that 56K resistor be connected between the 0.0033uF cap & the volume pot's lug 1 to ground in the first schematic?
yes, i believe so...as shown in the the 2nd schematic
Yeah, I just had a look at the patent and Jack Orman's schematic matches it with the corrected 470K resistor. The first one from Fuzz Central must be incorrect...still.
guilty as charged - I noticed this mistake some time ago, but forgot about it again - final correction done!
remember - blue border = wrong, purple border = right
Maestro FZ1 corrected schematic
4329619267_e4184ff6c5_o.jpg (73.89 KiB) Viewed 2236 times
"You've converted me to Cubic thinking. Where do I sign up for the newsletter? I need to learn more about how I can break free from ONEism Death Math." - Soulsonic
I built a breadboard version of the FZ-1 this afternoon though I used
PNP germanium transistors with gains ranging from 40 - 49
in place of the 2n270's. probably a bad idea because I couldn't
get any thing at all out of it. any one know where ( if anywhere )
I can get ahold of some 2n270's ?
A quick question about the correct schematic posted 6 posts above (the pink one).
Is that a junction after the first 20uF capacitor? Or does the signal from 470k to 2k2 not connect to the signal from the 20uF?
ringworm wrote:A quick question about the correct schematic posted 6 posts above (the pink one).
Is that a junction after the first 20uF capacitor? Or does the signal from 470k to 2k2 not connect to the signal from the 20uF?
No, the 3 components in question connect together to the base of the 2nd transistor.
reading the remarks on Glen's original patent states that the "missing" 470k resistor is actually a 470 Ohm resistor used for avoiding temperature problems on Q2.
can anyone verify that? 470R or 470K. the drawing in the patent designates this resistor as numbered 261 (probably because it was added later).
he also mentions that Base and Emitter voltages on Q1 should show a bias of -1.5V and a -3V bias on the collector of Q2, probably using a 1mA leaky 2N270 transistors.
I really want to build this pedal and it seems very hard to get the Voodoo out of this circuit and demistify the legendary sound.
Can anyone post a schematic with newer transistors which can be bought from SMallBear and change the circuit to get the right biasing on Q1-3?
THanks for the interest.
D
______________________________________________________________________________ K. Zustang
create something greater, something uncontainable. Make sure you are at a constant motion forward...
reading the remarks on Glen's original patent states that the "missing" 470k resistor is actually a 470 Ohm resistor used for avoiding temperature problems on Q2.
can anyone verify that? 470R or 470K. the drawing in the patent designates this resistor as numbered 261 (probably because it was added later).
well, this certainly looks like a 470k resistor.
Thanks man, I just finished breadboarding this circuit with trimmers on all 10k resistors and also a 20k on the 1.5k.
I did get a nasty buzz distortion which means I am in the right direction. I used some leaky AC128 trannies.
the fuzz pot still doesn't seem to work as it should because it has no effect whatsoever.
I'll try some more fiddling about and post my results.
K Zustang
______________________________________________________________________________ K. Zustang
create something greater, something uncontainable. Make sure you are at a constant motion forward...
what is the hfe of your current transistors? - i think i got mine going with around the 70-90 range, they don't have to be high gain (or leaky) in my experience. i was never one for checking voltages though. it's not really like a "proper" fuzz sound, you should get crude blasts of blatty fuzz, with a fast decay, and it will sound better with higher output pickups.
Could someone post some pictures with enclosure dimensions marked on them? I would like to make a repro enclosure and I would like to do it with accurate proportions. Pretty please.