Pigtronix Philosopher's Tone Germanium Gold LTD

jwpartain1 · Post by **jwpartain1** » 14 Jan 2011, 23:25

Hey FSB members, I haven't seen much discussion in the area of Pigtronix and I feel that they are coming up with some new ideas as far as effect pedals go. This is their compressor pedal, actually a limited edition version. The only thing that's different, from my understanding, is that a germanium transistor is used in the "GRIT" "engine" in this particular version.

I really like the way the switch and jacks are connected, seems reliable to me?

It looks to be extremely difficult to trace from just pictures, and past what I could do with the pedal in my hand.

Is that 12 diodes?

What’s the big black guy to the left of the 1uF 50V cap?

Is that the germ in the bottom left?

What’s with the empty TP3/TP2 connections on the component-side of the PCB?

Anyways, just wanted to share this cool pedal with everyone.
-JWP

Scruffie · Post by **Scruffie** » 14 Jan 2011, 23:34

jwpartain1 wrote:Hey FSB members, I haven't seen much discussion in the area of Pigtronix and I feel that they are coming up with some new ideas as far as effect pedals go. This is their compressor pedal, actually a limited edition version. The only thing that's different, from my understanding, is that a germanium transistor is used in the "GRIT" "engine" in this particular version.

I really like the way the switch and jacks are connected, seems reliable to me? It looks to be extremely difficult to trace from just pictures, and past what I could do with the pedal in my hand.

Is that 12 diodes?

I Didn't Count, Quite a Few though!

What’s the big black guy to the left of the 1uF 50V cap?

A Vactrol (The Optical Part)

Is that the germ in the bottom left?

Polarity Protection Diode (Probably a 1N400x), the Germanium looks to me to be attached to that Red LED, probably just a Germanium Diode in the Clipping... bit of a cop out.

What’s with the empty TP3/TP2 connections on the component-side of the PCB?

Not sure... something to do with alternative power or remnants of a different PCB version.

Anyways, just wanted to share this cool pedal with everyone.
-JWP

Thanks for Sharing! Nice to see what's in there, Howard Davis at it again.

DrNomis · Post by **DrNomis** » 15 Jan 2011, 00:01

Those TP3/TP2 connections are "Test Points",these are for adjusting certain voltages or signals in the circuit using trimpots,so that the circuit works correctly.....

Scruffie · Post by **Scruffie** » 15 Jan 2011, 00:03

DrNomis wrote:Those TP3/TP2 connections are "Test Points",these are for adjusting certain voltages or signals in the circuit using trimpots,so that the circuit works correctly.....

Ahhh of course, couldn't quite cotton on to that abbreviation.

jwpartain1 · Post by **jwpartain1** » 15 Jan 2011, 00:51

OK, cool.

These guys soldered these surface-mount parts by hand?!

How is it a cop-out if the germ is meant to be just in the clipping? I mean, what else would you use it for in this pedal? Just wondering

Thanks for all the answers to the n00b questions, still learning. So this looks to be a pain to trace then?

Scruffie · Post by **Scruffie** » 15 Jan 2011, 00:55

jwpartain1 wrote:OK, cool.

These guys soldered these surface-mount parts by hand?!

How is it a cop-out if the germ is meant to be just in the clipping? I mean, what else would you use it for in this pedal? Just wondering

Thanks for all the answers to the n00b questions, still learning. So this looks to be a pain to trace then?

These are through-hole parts like we all use, not surface mount, the resistors are 1/2 Watt so they're a bit smaller but still workable so yeah, they soldered it by hand.

Well... they charge alot more for a single Germanium Diode that probably cost $1 and use the Germanium Buzz word in the advertising to charge a higher amount for it where as really it's just clipping, not a Germanium Transistor which is what it could be construed as and what mojo hunters want.

It's not really a cop out, just marketing really.

Actually, not that I can trace myself yet, it might be possible for someone to yeah, might need a few more shots to be sure of all the tracks but it's a good start.

RnFR · Post by **RnFR** » 15 Jan 2011, 02:44

I still want to know where they get those switches. it looks like they are manufactured with the leads on. if not, they do a hell of a nice job of lead dress. why in the world would they need that massive filter cap? 2200uF?

and I kind it kind of curious that the DC input is right next to the signal input. it seems to be good practice to keep those things separated.

jwpartain1 · Post by **jwpartain1** » 15 Jan 2011, 03:24

This special version was actually 10 bucks more, while it was available at PGS. I also wondered why you would use a 50V cap? There's two..

Greg · Post by **Greg** » 15 Jan 2011, 04:06

RnFR wrote: why in the world would they need that massive filter cap? 2200uF?

G2D Cream Tone has a 2200uF cap on the power supply also.

jwpartain1 · Post by **jwpartain1** » 15 Jan 2011, 04:16

OK, so I rehoused everything, put my daughter to sleep, ate some dinner, and I really really want to trace this thing.. I've got it back out, but I need some help! In the area circled in red, are those connected there?

Greg · Post by **Greg** » 15 Jan 2011, 04:27

jwpartain1 wrote:OK, so I rehoused everything, put my daughter to sleep, ate some dinner, and I really really want to trace this thing.. I've got it back out, but I need some help! In the area circled in red, are those connected there?

It looks to me like the top 2 are, but not the other 2.. but just check with a multimeter.

Some pads are probably connected to the ground plane with small traces, so keep an eye out for that (they'll often seem to be pads that go nowhere).

jwpartain1 · Post by **jwpartain1** » 15 Jan 2011, 04:59

Man, this thing is puttin' a good whippin' on me. The parts are so close together. What do you reckon the signal should first see? I lose the signal under that fat cap on the left of the board..

mysticwhiskey · Post by **mysticwhiskey** » 15 Jan 2011, 11:38

I reckon the footswitch is wired like this:

Here's my incomplete attempt at tracing the circuit from the photos... there's plenty of missing connections since I couldn't see where they are connected. I haven't shown the ground planes yet, as I wanted to keep it clutter free until I worked out the missing parts.

If my footswitch wiring guess is accurate, then the input signal should first hit both the resistor soldered on the back of the footswitch connector, and C9, on it's way to U1 (I think it reads 'NE5532P', which makes it a dual opamp).

mysticwhiskey · Post by **mysticwhiskey** » 15 Jan 2011, 11:41

Forgot to mention that in lieu of the ground plane, I've started to mark the ground connections with a "G" symbol.

Hides-His-Eyes · Post by **Hides-His-Eyes** » 15 Jan 2011, 12:40

I think the switch is probably just heatshrunk.

jwpartain1 · Post by **jwpartain1** » 15 Jan 2011, 15:30

Below what you've got labeled as C12 there, that's a 15ohm (from what I can see: brown, green, black, gold, brown) resistor.

RnFR · Post by **RnFR** » 16 Jan 2011, 00:33

Hides-His-Eyes wrote:I think the switch is probably just heatshrunk.

yeah, you are probably right. i just remembered that some places sell those black switches. it does look nice, though.

PmCimini · Post by **PmCimini** » 17 Jan 2011, 02:06

Why so many different opamps?

RnFR · Post by **RnFR** » 17 Jan 2011, 03:45

Greg_G wrote:
RnFR wrote: why in the world would they need that massive filter cap? 2200uF?
G2D Cream Tone has a 2200uF cap on the power supply also.

what else is interesting is that it is a 10V cap, and this thing takes an 18V adapter. so, maybe it's filtering Vref. that should be somewhere around 9V.

jwpartain1 · Post by **jwpartain1** » 21 Jan 2011, 21:03

mysticwhiskey, could you post that Incomplete Layout in a file type I could edit in Msoft paint? Thanks! I'm slowly getting this.

Pigtronix Philosopher's Tone Germanium Gold LTD [traced]