madbeanpedals::forum

Projects => General Questions => Mods => Topic started by: jasonstomps on May 01, 2012, 06:17:18 PM

Title: Grapevine Mod –Rock/Rawk modes on a pot instead of DPDT?
Post by: jasonstomps on May 01, 2012, 06:17:18 PM
Hi,

Probably a silly noob question, but I was wondering if it would be possible to have the Grapevine Rock/Rawk modes on a pot (dual gang) instead of a switch.  Would it even work for sweeping between the Rock/Rawk modes? 

Any thoughts, comments, suggestions?

Thanks
Title: Re: Grapevine Mod –Rock/Rawk modes on a pot instead of DPDT?
Post by: jkokura on May 01, 2012, 06:58:33 PM
The switch is a bit more complicated than you might think. One one setting, it involves two capacitors in two areas of the circuit. In the other setting it involves three capacitors and two resistors in one area while removing both of the caps from the other setting What I'm saying is that it's not like switching between two caps, or two resistors, there are a lot more parts involved and in two different areas of the circuit.

This stuff works well on a switch, not on a pot.

Jacob
Title: Re: Grapevine Mod –Rock/Rawk modes on a pot instead of DPDT?
Post by: jasonstomps on May 01, 2012, 07:18:42 PM
Aw nuts.  I thought I could get away with using a dual-gang like this, but you're right, probably works much better on the switch.

(http://i226.photobucket.com/albums/dd172/jasonsguild24/Rock-RawkMod.jpg)

Not that having the toggle switch is a bad thing, I just always want to turn knobs...
Title: Re: Grapevine Mod –Rock/Rawk modes on a pot instead of DPDT?
Post by: jkokura on May 01, 2012, 07:22:56 PM
In theory you could do that, but I wonder about it's effectiveness.

If you build it, try it on a breadboard first. Also, be aware that you need to have at one extreme be the inclusion of only C2 and C5 in the circuit removing C6-8/R7-8, and at the other extreme of the pot be their exclusion while only having C6-8/R7-8.

Jacob