Another ancient fuzz schematic unearthed

[ErikMiller]

From Byron Wels' How to Repair Musical Instrument Amplifiers

Note the supply voltage.

[/i]

[onboard]

Yeah man, 1.5V of pure power! And a Heathkit to boot! :wink:

Seriously, last time I went hunting for a part at a local mom & pop shop the fellah said "Wow, you're going back to the days of Heathkit stuff"...makes me wish I still had that crystal AM radio.

I have to ask, are the diamond shaped "A", "S", and "D" points on the schem just connection references I wonder?  (I fell silly asking)

Looks worth BB'ing just for curiosity's sake!

[petemoore]

I see no reason not to.
 I also see no reason it couldn't be run at higher voltages, as long as the components are rated for that.
 What strikes me interesting is how they could get the signal to swing enough to get clipped and have enough output...because I haven't figured it out and am suggesting fodder for entertainmental discussion.
 Stick a Voltage regulator on it with a pot or Voltage other varying device???

[MartyMart]

Is that a tiny " . " to give 1.5 v or is it "15 volts" ?? that sounds more like it does'nt it ?
Marty.

[puretube]

the diamonds seem to be connector-designations on PCB to outboard components...

[bwanasonic]

The spacing of the numbers makes me think "1.5" vs "15" . Also 1.5 is more likely as this would mean a single dry-cell, maybe even a "C" or "D" cell.

Kerry M

[Gilles C]

It has a gain of 3, so I suppose that it needs a supply of 1.5V to clip/distort.

With a supply supply like 9V, it would need more gain to clip.

I played with that kind of circuit a while ago, but with a FET at the input, and with a gain of 2 (I needed a clean input buffer), when I was lowering the supply, it would start to clip the top of the signal, not as square as a fuzz, but not as round as a FET.

The first prototype on this page uses a modified version of that input buffer

http://members.tripod.com/gillcar/id24.htm

Gilles

[guitarhacknoise]

man, that link was straight pop-up city!
any way,
yeah,  it's a 1.5v AA battery and the diamonds with letters in 'em are for the off board connections.
I really like this fuzz, kind of a nirvana, bleach era sound (if i have to compare) the box on this guy is tough, cast IRON? heavy as hell - about 3lbs. of housing!
as far as the transisters in mine go, I don't recognize these #'s:
  q1: 417-91 / T1805
  q2: 417-201
here is another schem.   http://www.muzique.com/schem/heathkit.gif

[zachary vex]

you can see there's a + sign in one of those diamonds too... my guess is that "A" represents the audio input to the circuit, and whatever the other letters stand for, one is more trebly output than the other.

*hmph.  well, anyway, this post was to answer someone's question and apparently they took their posted question down.

[guitarhacknoise]

D= lug 1 - tone pot
S= lug 3 - tone pot
A= wiper -fuzz pot
+= +1.5v
 -= stereo jack ground / - 1.5v
easy enough, they have these letters printed on the board so you know which wire goes where by matching it to the schematic :shock:  well you know what I mean, so any one could assemble it with out any electronics knowledge what so ever.  :wink:

[Gilles C]

man, that link was straight pop-up city!

Yeah,  :evil: That's why I started moving it to a paid host. Tripod has too many pop-ups these days...

I'm almost done with it.