Fuzz Face switch change

Started by maybury, November 08, 2006, 07:09:43 AM

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maybury

I have an original 60's Fuzz Face and I suspect that the foot switch is faulty as my VOX Wah Wah pedal will not work (only gives a thin sound) when the fuzz face is switched off. It's OK when I have the Fuzz Face on or if I use a different distortion pedal. So I have bought a 3PDT switch to replace the existing switch but I can't find a wiring diagram to show which wire goes on which tag from the Fuzz Face to the 3PDT. The diagrams I have seen seem to have less wires coming from the Fuzz Face to the switch.

Any ideas on either the problem or the switch wiring would be much appreciated.

Cheers.

yeeshkul

#1
These are pins on your 3PDT switch (9 pins)

1a - 2a - 3a
|     |     |
1b - 2b - 3b
|     |     |
1c - 2c - 3c

Lets say that the switch will be:
1. OFF    1a,1b / 2a,2b / 3a,3b connected
2. ON   1b,1c / 2b,2c / 3b,3c connected

Make sure that pins are being shorted as described above. If you turn your switch by 90° it won't work (it happened to me yesterday, hehehehe)

Then
1. connect one wire from the input jack (signal pin) to the 1b pin
2. connect one wire from the output jack (signal pin) to the 3b pin
3. connect pins 1c abnd 3c - right on the switch
4. connect 1a to the input of your circuit
5. connect 3a to the output of your circuit

so when your FF is
1. ON then signal goes like this: input jack-1b-1c-3c-3b-output jack - unharmed
2. OFF then signal goes like this: input jack-1b-1a-FUZZ FACE-3a-3b-output jack - fuzzfaced


leave out the 2a,2b,2c - those are usually used for things like LED

that should be it

yeeshkul

#2
There will be one wire coming from and one wire coming to the FF circuit. The trouble with true bypass switch is that it may pop when switched on - because of the input cap that emptying is itself at that moment - while the output cap does the job through the volume pot (that is connected to the ground)

To get rid of the pop:
1. Solder 2.2M resistor between ground and some place before the input cap - the charged-cap current will be pulled down out of the signal way and so there will be no pop.
2. there is another way to connect 3PDT switch and that one uses one wire connected to ground ... and it is said that it helps too.

Do not solder the input 2.2M resistor on your input jack (like silly me), cus it is no use when disconnected at the same time as the input cap.

maybury

Thanks for the quick reply!

On my Face Fuzz I also have 2 wires from the 470k volume pot to the current switch with one of these wires connected to the same wire that goes to the board!

Current switch layout -

      |(1)       |(2)

      |(3)       |(4)

      |(5)       |(6)

(1) - purple wire from the input socket and jumper link to (6)
(2) - brown wire from the 470k volume pot and pink wire from the board (don't know how you tell if this wire from the board is in or out?)
(3) - red wire from the output socket
(4) - red wire from board (again don't know how you tell if this wire from the board is in or out? Guessing it's out as it's the same colour as the wire from the output socket?)
(5) - blue wire from the 470k volume pot
(6) - jumper link to (1)


Also found out that there is an oddity with the Fuzz Face / Vox Wah Wah combination that is apparantly well known! Quick fix is to put the Fuzz Face before the Wah Wah in the pedal chain.

Cheers.

yeeshkul

#4
Ok, you just described the type of wiring that may prevent your DPDT from popping since the pink wire is the ground wire - when you turn your FF off the input cap will be emptied to the ground through the pink wire. The pink wire (ground) is connected to the pot's ground-pin (brown wire) - that's the way to make sure the circuit is properly grounded.
It should be working like this.

FF ON
the signal goes like: input jack-(1)-(6)-(4)-circuit-volume pot signal pin-volume pot centre pin-(3)- output jack
FF OFF
the signal comes from input jack-(1)-(3)-output jack and at the same time (4) is shorted to (2) - the input cap is shorted to the ground

yeeshkul

as for the thin sound - make sure the pink wire is properly soldered. this happend to me as well. no ground no sound ...

maybury

Really appreciate your help here.

So if I understand this so far -

Current switch pin (1) input jack purple wire goes to 3PDT-1b

Current switch pin (2) input pink wire from board goes to 3PDT-1a
Current switch pin (2) volume pot brown wire goes to 3PDT-?

Current switch pin (3) output jack red wire goes to 3PDT-3b

Current switch pin (4) output red wire from board goes to 3PDT-3a

Current switch pin (5) volume pot blue wire goes to 3PDT-?

Current switch pin (6) jump 3PDT-1c and 3PDT-3c

I'm not sure which pins on the 3PDT the brown and blue wires from the volume pot go to?

Cheers.

yeeshkul

#7
Well,it depends what you gonna use
1. The wiring described by me + 2.2M input pull down resistor or
2. The wiring described by you, which is clever and doesn't need any pull down to get rid of the pop (i would recommend this one). This one should be working the way you described. It was flawless.

In case you wanna use the standard wiring + pull down then:

First let's have a look at the 470k volume pot:
It should have all the pins busy

  (1) (2) (3)
/-----------\
|                |
|                |
\_______/

(1) "some colour" wire  - this is signal output from the circuit to the pot
(2) blue wire - volume-modified signal from the pot towards the output of the box
(3) brown wire - ground

rem: the other pot (fuzz) should have also all the pins busy:
- one side wired to the circuit
- the other side either grounded to the socket, the other pot or wired to the circuit ground
- the center one either to the circuit or via cap to the right one.

and now how to connect all the things:

1. Pink wire (ground must be connected to the ground ring of the input or output jack socket) - basically it is connected to the enclosure this way. In case the enclosure is not made of metal, you have to connect also both ground rings of the jack sockets (in addition) - measure it. I am nearly sure that your troubles are caused by the circuit ground not being connected to the sockets.
2. Purple wire to 1b - input from the input socket
3. Brown wire from the pot to the same place as the pink wire - either circuit or socket end - this is a ground wire
4. Red wire from output socket to 3b
5. Red wire from the circuit to 1a - circuit input
6. Blue wire from the pot 3a
7. "some colour" wire from the circuit to the pot - circuit output

if the switch audibly pops when turned on then you have to add a pull down resistor as described above ...

petemoore

#8

 Here's a PNP Pos Gnd FF [probably yours is same] showing the switching for input/output and bypass...see below
 look through the eyelets on your 3pdt, then look down on it from the top without rotating it 1/4 turn, IOW everything looks the same/same but the switch can easily be miswired...then you'll have to 'spin' it 1/4 turn and rewire it...looking from the top the eyelets sight your shirtbutton.
 You might wanna add pulldown resistors [if it has none] to the circuit's bypass switch or board to prevent popping when bypassing/enabling.
 How does it sound? [is better answered after some FF tweeking Exp.]
 OT Probably an early GE FF profit-clone...not much/no time has been spent tworking it to sound 'so', I'd at least measure the transistor pin voltages to establish Whether it is biased / bias it if I thought I was going to try to *use it.
 *Geo Technology of the Fuzz Face
 For ampplication, transistor, circuit function info etc.
 I referenced this article RG wrote many times, going around the 'stumpies', but coming back to the parts with maths' etc I couldn't get through, then diggin up on the 'other pages' and spending time 'stump pulling' on the more technical areas ... your comprehension is different than mine...anyway a read through the article's text tells allot about FF usage.
 
 
 
Convention creates following, following creates convention.

petemoore

#9
  You  have DMM ???
  Since your new to switches it's a good idea to take pencil/paper/DMM and plot what the switch does on paper.
  Stick the switch in any box w/Sw hole, cardboards fine, just to hold it still...lugs up.
  Looking down at the lugs on the 3pdt, the eyelets in the lugs should aim at you, if not, turn the switch 1/4 turn.
  testing w/dmm or low voltage test light circuit
  you'll see
  *        *          *
   l         l           l
  *        *          *

 *         *          *
   each 'l' represents two switch lugs connected, looking only at the top and middle rows, you have three *separate sets of two lugs [*L to R] which connect/disconnect simultaneously.
  Hit the switch and the three separate 'l' [connections] all move to between the middle and bottom row.
  You need only two columns to get true bypass.
  The Right *Column [up/down] is the first SPDT. single pole double throw, pole is in the middle...that goes to...[we'll assign it] Input jack tip, and recieves the guitar pickup as source, connect the [well assign it] to the bottom left lug.
  Connect a jumper wire across the top right and left lugs, the right middle lug to output jack tip. You can see how there's a straight connection between input and output jack tips when sw is in BP mode.
  the bottom right connection gets the circuit output.
  If the switch is working right:
Signal comes in the left midde and goes through BP jumper to right middle.
OR..Signal comes in the left middle, goes through the circuit to right middle.
 
Convention creates following, following creates convention.

petemoore

#10
  GGG has bypass wiring info..Diagrams !
  Edit... OUCH...here's the PNP Pos Gnd Schematic !!!...sorry
  http://www.generalguitargadgets.com/diagrams/fuzzface_sc_pp.gif
Convention creates following, following creates convention.

maybury

Thanks for your input. Sorry I didn't get back earlier but my internet service went down!

I'll replace the switch tomorrow and let you know how it goes.

Cheers.