madbeanpedals::forum

Projects => General Questions => Mods => Topic started by: ImpossiblyFunky on March 04, 2012, 07:05:14 AM

Title: Dirtbag trails?
Post by: ImpossiblyFunky on March 04, 2012, 07:05:14 AM
Hi guys,

I've done some searching around the boards for this, but didn't come up with much.  I'm getting ready to build up a Dirtbag and would like to include a mod to allow the delay to trail off after the effect is disengaged.

I'm curious if this is possible, if it's been done, and if anyone might have any suggestions on how to go about doing it? 

Any input is very much appreciated.

-ImpossiblyFunky
Title: Re: Dirtbag trails?
Post by: madbean on March 04, 2012, 01:41:19 PM
Probably the simplest way to do that is wire the bypass switch between IC1A and IC1B and then connect the effect output to the output jack and the effect input to the input jack.

So, you could leave C3 and R4 off the PCB, use the empty pads as your connection to the switch. You need to add C3 and R4 in the return path to the board via a small amount of perf attached to the switch. You might need an output cap for IC1A, too, but maybe not.


from PCB ------ switch in - switch out --- C3/R4 -------- to PCB

I don't know if you will get any popping switching it out this way. If you add a pulldown and  decoupling cap from pin1 of IC1A that might fix any popping that occurs.

Something more complicated, yet elegant, would be like a transistor-based switch, where you make an NPN act like a series resistor. So, when the base of the transistor is pulled to ground, the signal stops at the collector, and when the base goes to VC, it acts likes a resistor and lets signal flow from the collector to emitter. This is closer to what I'll be doing with the Aquaboy Deluxe and its tails feature, although I have not actually gotten around to working the thing up yet.


ANYWAY, point being is yes it is definitely possible but I personally don't have an exact procedure or wiring diagram drawn up for it at the moment.
Title: Re: Dirtbag trails?
Post by: ImpossiblyFunky on March 05, 2012, 03:46:12 PM
Hi Madbean,

Thanks for the insight.  This, along with some other things I've been reading this weekend are encouraging me to change course a bit.  The DBD is going to be a challenging build as it is, so I think I'm going to just do it stock.  I've read some things about the AuquaBoy Deluxe and it looks like that's going to make for a great build.  I'll be the first in line to snag one of those when you have boards for sale.

-ImpossiblyFunky