Germanium OCD

[Robert]

Do you have a DMM and / or audio probe ? Try soaking it in Palmolive.

Will this work? Palmolive? I can see where that might help with the friction.

 

[fig]

Ribbed...groovy!

 

[ClassicFuzz]

A very helpful thread. Thanks for all your input. I think I might give this a go with a V2 layout. How could one implement a switch to switch between V2 and Custom GE?

 

[Robert]

Assuming I am correct about the connection of the diodes, you would just wire up a DPDT switch to jump across both diodes.

 

[ClassicFuzz]

Assuming I am correct about the connection of the diodes, you would just wire up a DPDT switch to jump across both diodes.

so basically drill them together asymmetrically and connect them to lug 1 & 4 of the switch and then one wire between lug 2 and source (transistor 1) and between lug 5 and drain (trainstor 2), right?

 

[ClassicFuzz]

Those Ge diodes have a single green band, yes? That would make them Д9Ж (D9J). They're hard-wired to the MOSFETs (Q2 & Q3). The diodes, MOSFETs and wires are glued down as a strain relief. 'Cuz clear goop would just be silly.

Sure are a lotta extra parts on that board compared to an OCD or Alpha Drive.

Whatever kind of diodes these may be Mike Fuller wrote on Facebook that the Forward Voltage is 0,35 V.

 

[ClassicFuzz]

I am still scratching my head. How would I wire a dpdt switch if I'd be using this layout from Effects Layouts? And where would I cut a trace?:

 

[manfesto]

I am still scratching my head. How would I wire a dpdt switch if I'd be using this layout from Effects Layouts? And where would I cut a trace?: View attachment 32304

you wouldn't need to cut a trace, you'd use two of the pads of Q3 and Q4 since those are what you're modifying.
EDIT - I'm wrong and will rephrase once I find some paper

 

[manfesto]

I am still scratching my head. How would I wire a dpdt switch if I'd be using this layout from Effects Layouts? And where would I cut a trace?: View attachment 32304

So here's one way to do it, although it takes four 2N7000s instead of two, which I'll figure out next, but this is basically how you'd do clipping mods where you just fly different sets of diodes on the DPDT switch itself

 

[manfesto]

I am still scratching my head. How would I wire a dpdt switch if I'd be using this layout from Effects Layouts? And where would I cut a trace?: View attachment 32304

oh actually this way's much easier and I was overthinking it.

EDIT: the diodes are backwards in my drawing, my bad. Source should connect to the cathode of the D9K, not the anode!

 

[Robert]

 

[ClassicFuzz]

oh actually this way's much easier and I was overthinking it.

EDIT: the diodes are backwards in my drawing, my bad. Source should connect to the cathode of the D9K, not the anode!
View attachment 32310

Nice, this looks good. With Q3 & Q5 "source" you mean DG-Pad?

 

[manfesto]

Nice, this looks good. With Q3 & Q5 "source" you mean DG-Pad?

No I mean the actual S leg of the transistor, you'd solder in D and G, then bend the S leg up and solder a wire from it to the center lug of the DPDT switch.

EDIT: also from the EffectsLayout layout, it's Q3 and Q4, not Q5

 

[ClassicFuzz]

No I mean the actual S leg of the transistor, you'd solder in D and G, then bend the S leg up and solder a wire from it to the center lug of the DPDT switch.

EDIT: also from the EffectsLayout layout, it's Q3 and Q4, not Q5

My mistake, I meant Q4 and wrote Q5

Like this?:

 

[manfesto]

My mistake, I meant Q4 and wrote Q5

Like this?: View attachment 32313

not quite, you won't be touching the "G" pads at all (or rather, you'd solder the "D" and "G" like normal into the board).

You won't solder the "S" legs into the board, instead you'll bend them up and solder wires from them to the center lugs of the DPDT switch.

Then the "S" pads on the board will be wired to the bottom lugs of the DPDT switch.

Both diodes will be facing the same way, with their cathodes attached to the top lugs of the DPDT switch.

 

[ClassicFuzz]

not quite, you won't be touching the "G" pads at all (or rather, you'd solder the "D" and "G" like normal into the board).

You won't solder the "S" legs into the board, instead you'll bend them up and solder wires from them to the center lugs of the DPDT switch.

Then the "S" pads on the board will be wired to the bottom lugs of the DPDT switch.

Both diodes will be facing the same way, with their cathodes attached to the top lugs of the DPDT switch.

Ok, now I understand. Thanks

 

[mdc]

oftentimes there is only a thin layer of bullshit between that $200 pedal and the one you make in your basement for $40.

That layer could generally be called "valuing your labour and someone else's R&D at $0/hr."

 

[manfesto]

Ok, now I understand. Thanks

View attachment 32318

If you’re using D9 diodes that’s perfect, since the stripe is on the anode on those diodes and you want the cathodes connected to the top lugs

If you’re using 1N34s or others, the diodes will be flipped from that diagram wit the stripes pointing up, either way it’ll be good to test and double check

 

[ClassicFuzz]

If you’re using D9 diodes that’s perfect, since the stripe is on the anode on those diodes and you want the cathodes connected to the top lugs

If you’re using 1N34s or others, the diodes will be flipped from that diagram wit the stripes pointing up, either way it’ll be good to test and double check

Just built it and it works. I used D9 diodes with the same voltage and it sounds the same. Thanks again for all your help.

 

[Locrian99]

I’ve got a clone of 1.4v I built (which is the version with the one germanium diode). I decided to make a switch on mine to take bypass the diode. I feel like I wasted the switch, the difference is very subtle, it’s there but it’s subtle. I used a 1n34 for the germanium. I also dinked around with doing an on off on with the 1n4148 again the difference is there but it’s so subtle I question the point. But hey the pedal looks cooler with an extra switch right.