Mark Hammers Woody

[gtr2]

Cool build thanks for sharing.  Definitely an interesting projects to remember for the future.

[irmcdermott]

OK. Here's where I look like a fool for asking this question....

I've never seen a power set up like this before, with the -9V going to a resistor, a cap, and then there is a separate GND. Can someone explain to me what is going on there? I need me some edumacation

Also, Scruff, if you read this. It looks like Hammer's version is for two 9Vs, but you seem to be running from 1. Also, For the three knobs, did you just break up the dual-ganged pot in his original?

I'm interested in this pedal and may work on my own layout, it I can figure out what is going on

Ian

[alanp]

Not sure what's going on in this circuit, but in synth-diy stuff the common power supply of choice is -15V, GND and +15V. +5V is commonly included for logic circuitry.

[Scruffie]

OK. Here's where I look like a fool for asking this question....

I've never seen a power set up like this before, with the -9V going to a resistor, a cap, and then there is a separate GND. Can someone explain to me what is going on there? I need me some edumacation

Also, Scruff, if you read this. It looks like Hammer's version is for two 9Vs, but you seem to be running from 1. Also, For the three knobs, did you just break up the dual-ganged pot in his original?

I'm interested in this pedal and may work on my own layout, it I can figure out what is going on

Ian

Bi-Polar split to V.Ref, that's how V.Ref works, instead of 9+ & 9- imagine that V.Ref is 0, 9V is 4.5V & Gnd is -4.5V, get it? Hence, Virtual reference, the chip thinks it's 0V where as really, its 4.5V

And yes the dual gang is broken in to two pots, works better that way.

The resistor drops the voltage a bit and forms a low pass filter with the cap to cut down on power supply noise... and don't try and follow the PCB, it's 4 layer so there's internal connections you can't see.

Not sure what's going on in this circuit, but in synth-diy stuff the common power supply of choice is -15V, GND and +15V. +5V is commonly included for logic circuitry.

Completely different, as mentioned above 

[bigrigg]

OK. Here's where I look like a fool for asking this question....

I've never seen a power set up like this before, with the -9V going to a resistor, a cap, and then there is a separate GND. Can someone explain to me what is going on there? I need me some edumacation

Also, Scruff, if you read this. It looks like Hammer's version is for two 9Vs, but you seem to be running from 1. Also, For the three knobs, did you just break up the dual-ganged pot in his original?

I'm interested in this pedal and may work on my own layout, it I can figure out what is going on

Ian

Bi-Polar split to V.Ref, that's how V.Ref works, instead of 9+ & 9- imagine that V.Ref is 0, 9V is 4.5V & Gnd is -4.5V, get it? Hence, Virtual reference, the chip thinks it's 0V where as really, its 4.5V

And yes the dual gang is broken in to two pots, works better that way.

The resistor drops the voltage a bit and forms a low pass filter with the cap to cut down on power supply noise... and don't try and follow the PCB, it's 4 layer so there's internal connections you can't see.

Not sure what's going on in this circuit, but in synth-diy stuff the common power supply of choice is -15V, GND and +15V. +5V is commonly included for logic circuitry.

Completely different, as mentioned above 

The dual gang audio pot....how do you wire in the 2 regular pots to replace. Typical pcb one layer would show the 3 lug connection on the board. I've read more than once, this is a good mod and improves the "tweak" ability. Thanks very much.

[Scruffie]

The dual gang audio pot....how do you wire in the 2 regular pots to replace. Typical pcb one layer would show the 3 lug connection on the board. I've read more than once, this is a good mod and improves the "tweak" ability. Thanks very much.

Well look at the schematic, where as it shows two halfs of a dual gang, you just use two single gang pots, simple as that.

Some people like to wire the trimmer as a pot too to help suit different guitars.

[Scruffie]

I have one spare PCB for this (in fact the only spare likely to ever exist) if any of you guys want it, $18 shipped anywhere.

You can see the layout in the first pic and how it fits with everything, 4-layer express PCB proto, leaded pads, very nice quality, one small mistake on the layout in that the polarity protection diode was sized wrong for thicker 1N400X diodes (I just used a 1N914... better than nout).

Wrong section but seeing as it's one specialist item and all the info's here, figured it'd be okay.

[DutchMF]

Surprised nobody jumped at this....... I'd be interested, but as I didn't join in on the thread in the beginning (think I wasn't even a member when the thread started) I think if any of the guys that did would want it, they should have it. But if there aren't any other takers...... Please!

Paul

[LaceSensor]

I'm interested what's that in Gbp?

[Scruffie]

I'm interested what's that in Gbp?

About £11.

[DutchMF]

Lace, if you want it, take it man, you were on to this last November.

Paul

[LaceSensor]

cool, thanks
gentlemen and scholars round here