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corrected Maestro FZ-1 schematic?

PostPosted: 22 Sep 2010, 01:34
by LucifersTrip
I did a bunch of searches and can't seem to find conclusively the correct schematic for the original 3v FZ-1. Which is correct?

It's a little different all over the place, but these seem like the best shots with the 56K's in different spots:

From forum:


...and this originally did not have the 470K and someone commented that is was missing:
Image

In the first, what's the purpose of the 56K & 10K in parallel? Did someone run out of 8.5K's?

thanx

Re: corrected Maestro FZ-1 schematic?

PostPosted: 22 Sep 2010, 03:44
by jrod
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?

Re: corrected Maestro FZ-1 schematic?

PostPosted: 22 Sep 2010, 12:07
by LucifersTrip
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

Re: corrected Maestro FZ-1 schematic?

PostPosted: 22 Sep 2010, 14:37
by jrod
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.

Maestro FZ-1  [schematic]

PostPosted: 24 Sep 2010, 15:44
by royaltoots
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

Image
Maestro Fuzz-Tone FZ-1correct schem by simonm1965, on Flickr

Here's my completed build - I used a scribbled-on Orman schem to build it, so the mistake didn't make any difference:

Image
Image

Re: corrected Maestro FZ-1 schematic?

PostPosted: 24 Sep 2010, 22:18
by LucifersTrip
excellent...looks great....thanx for confirming the correction

Re: corrected Maestro FZ-1 schematic?

PostPosted: 24 Sep 2010, 22:43
by Barcode
Just a point of note, there is a "1" and a "1a" version of this circuit. One ran off 1.4v, one off 3v. They vary slightly.

Re: corrected Maestro FZ-1 schematic?

PostPosted: 25 Sep 2010, 01:25
by RnFR
and after all this time! :slap:

topics merged.

Re: corrected Maestro FZ-1 schematic?

PostPosted: 25 Sep 2010, 12:36
by Electric Warrior
never trust a fuzzcentral schematic :mrgreen:

great to see somebody is organzing the information here. :applause: keep up the good work!

Re: Maestro - FZ-1

PostPosted: 07 Nov 2010, 11:25
by spazztech
new to the board - hello

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 ?

thanks -

Re: Maestro - FZ-1

PostPosted: 08 Nov 2010, 16:52
by ringworm
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?

Re: Maestro - FZ-1

PostPosted: 08 Nov 2010, 17:32
by jrod
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.

Re: Maestro - FZ-1

PostPosted: 09 Nov 2010, 10:36
by ringworm
Thanks for that.

Re: Maestro - FZ-1

PostPosted: 21 Nov 2010, 23:22
by kzustang
HI everybody,

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

Re: Maestro - FZ-1

PostPosted: 22 Nov 2010, 01:22
by Electric Warrior
kzustang wrote:HI everybody,

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).


Image

470k

Re: Maestro - FZ-1

PostPosted: 23 Jan 2011, 20:14
by kzustang
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

Re: Maestro - FZ-1

PostPosted: 03 Feb 2011, 00:50
by royaltoots
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.

Simon

Re: Maestro - FZ-1

PostPosted: 08 Aug 2011, 18:08
by Rolbista
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.

Re: Maestro - FZ-1

PostPosted: 08 Aug 2011, 21:02
by John Lyons
These are made with the same dimentions.
Might save you some time.
http://www.pedalenclosures.com/Products/tabid/69/p/Prism-I---Unfinished/ProductID/20/Default.aspx

Re: Maestro - FZ-1

PostPosted: 09 Aug 2011, 15:02
by Rolbista
That's nice, but the point is I have a lot of time and i like tinkering with metal. Besides, shippin would probably cost me more than the enclosure