Questions about Frost drive AKA VFE Ice Scream

[Chuck D. Bones]

Well Friggy-Diggy! Almost makes me want to build another one. After I get done with the 7 or 8 in the queue.

 

[Robert]

Build docs updated with link to C100K and info about component value substitutions.

 

[Mike McLane]

So if going with C100K. . . C3 = 4.7nF, C4 = 12nF, R4 & R5 = 10K. . . for Chucky's wider tuning 6.8, 18, 6.8K respectively.

 

[Mike McLane]

BTW FYI, just DL'd the updated Build Docs and didn't notice the revisions "PedalPCB" noted in the comment immediately above.

 

[Robert]

It's there, Page 2.

http://pedalpcb.com/docs/FrostDrive.pdf

 

[Barry]

Looks like I have the old boards, so looks like I need C100K dual with solder lugs, would A or B taper if I can find them work as well?

Edit: I have A10k and A100K dual gang on the way (went ahead and got some in B taper as well)

 

[Chuck D. Bones]

If you use B taper, the top end of the freq range will be crowded at one end of the rotation. If you use A taper, then don't reverse the pot wiring, wire it straight to the board. The high frequencies will be at the CCW end of rotation, but it will all be evenly spread. If you use the A10K, then you don't need to change any component values. HOWEVER, C3 should be 47nF. In the build docs dated 09.01.19, it is wrong in the BOM & schematic. It is also wrong on the silkscreen.

 

[MightySmallElectrons]

Am I understanding correctly that the Dual A10k option will just make the knob function backwards to the original? My understanding is that the taper is the same just reversed?

 

[Chuck D. Bones]

Yes and yes.
A taper spreads out the CCW end of rotation. Noon is 15% of the resistance (measured from pin 1 to pin 2). C taper spreads out the CW end of rotation. Noon is 85% resistance.