#1
So, yea, I want my wah pedal to control my volume when off. It's a Build Your Own Clone kit that I put together a couple of years ago.

Here's the PDF instructions I used to build it which includes a schematic on the second to last page:

http://byocelectronics.com/wahinstructions.pdf

I posted a thread on their forums about this since I've got help there in the past, but that was over a month ago and I still haven't gotten a reply. Their forums seem to be almost dead. The rest of this post is a slightly altered copy of that post.


I did a little search and saw a thread on the BYOC forum where someone mentioned having the wah on all the time and lifting the 4.7 cap to make it kinda act as a volume. This thread is mostly just to make sure I do it right and make sure it'll work as I want.

So what I need to do is get rid of all the wires going to the 3PDT switch and wire the tip of the input to the IN on the board, wire the tip of the output to the OUT on the board, lift one leg of the cap labeled 4.7 np and wire that to the middle lug of one of the rows on the switch and then run a wire from the hole that leg is supposed to go in to one of the outer lugs on that same row of switches? Then I would have two spare rows on the 3pdt to play with lights or whatever?

So, will this work as I'm intending? Will there be a difference in tone when it's in the off position? I know that by now it would've been faster to just rewire it and see if it works, but I just really don't want to mess with it if it's not going to sound right since it's working perfectly fine as it is. I'm just looking to give it a little more functionality since I don't use the wah very often.


If what I'm thinking about doing isn't going to work or mess with my tone or volume when "off" is there another way I could modify it to do what I want? I'm fairly good at putting circuits together, even just using perf board, but I don't really understand how they work so I don't know how to modify things without someone telling me how to do it.
Last edited by The4thHorsemen at Nov 20, 2013,
#3
Quote by Invader Jim
You got it, man. It won't change the tone of the sound any more than when the wah is on.


Ugh, when my wah is on it sounds WAY different. It doesn't sound bad, but I don't want it to sound like that every time I turn on my effects loop. I guess I just need to mess with all those trim pots some more? Should it be possible to get it to sound exactly the same, or at least really close to what it sounds like off? Last time I messed with the trim pots I spent like 45 minutes playing with them, got irritated, and just found something that sounded "good ***ugh".


edit: also, why the hell didn't I post here a month ago?
#4
Messing with the trimpots won't do you any good if you don't know what you are changing. Is this thing true bypass or buffered bypass (stock crybaby style)?
Last edited by Invader Jim at Nov 20, 2013,
#5
it's true bypass, and all the trimpots are labeled on the circuit board. I've got gain, mids, bass, Q, and buffer volume. I opened it up and I'm messing with it right now. I found this thread on the BYOC forums with some stock resistance values

http://byocelectronics.com/board/viewtopic.php?f=33&t=11207

But it says to put them at stock value before installing them. Are my measurements going to be wrong if I check with my DMM with em still on the board, or are there other things in parallel that'll cause my measurements to be wrong? I hate desoldering stuff from a circuit board, but if I have to, then ok.
#6
When taking resistance measurements the component should always be out of the circuit. I don't have a schematic on hand to see which pots can be left in but if you have to remove one you might as well remove them all.
#7
Damnit, I set the gain, mids, and bass trim pots to the settings suggested in the byoc forum, and got to the Q trim pot and I'm getting a 0.L reading no matter where it's turned to.

This is why I hate desoldering small components like that. It seems like there's a huge chance for something to screw up.

I guess it's time to send an email to try to get a hold of another one.
#8
Well have you tried looking at the values of the trimmers and the "stock" resistance and eyeballing it? Say you have a 100k Q trimmer and the stock value is 33k, so just set the trimmer to about a third of its rotation. It'll get you in the ballpark so you can tweak by ear from there. Remember that pots only rotate about 270 degrees or so.
#9
Well, if I'm getting a 0.L reading that means the pot is screwed though, right? Isn't 0.L basically infinite resistance? And when turning the pot it feels like something's grating in there, so I'm guessing when I desoldered it just now I must have messed it up somehow.

Edit: Oh, I just noticed that in my previous post I failed to mention that I took all the pots out of the pcb so that I could accurately measure them
Last edited by The4thHorsemen at Nov 20, 2013,
#10
Oh. Hm. Grating is never good with pots. If you are reading OL anywhere with a pot, it's definitely tits-up. Pots and trimmers are fairly easily damaged by excessive heat. If I recall correctly, BYOC uses double-sided boards as well. Those definitely don't help things.
#11
Yup, they're double sided, and I've never been great at getting components off a board. I have a spring loaded solder sucker, but there's usually a little solder on the component side that doesn't want to come out. But yea, I went ahead and sent an email to BYOC, I'm sure they'll help me out. From what I remember I think their service was pretty good.
#12
That's what I've heard as well.

You may want to invest in a desoldering iron. They are orders of magnitude better than those cheesy spring-loaded deals. Double-sided boards are still a bit tricky though.

Desoldering braid may work just as well or better but I've never been able to use it worth a flip.
Last edited by Invader Jim at Nov 20, 2013,
#13
I might get a desoldering iron eventually, but I don't really mess with this stuff very often any more, so I'll probably continue to forget about it until I need it, then think oh I need to get one of those and repeat. Are the ones they sell at radioshack any good? Maybe next time I'm in there I'll see one and remember to get it.

Yea, I've tried desoldering braid in the past and it's always just pissed me off.
#14
The ones at RadioShack are ok, but a new tip costs as much as the whole iron. You have to keep the tips really clean or the solder will eat them up. If I had the cash I'd invest in a good quality one with an alloy tip rather than the cheap plated/tinned/whatever tips. Plated tips (for any type of soldering iron) need constant cleaning and filing. You NEVER file an alloy tip.

Just FYI, if they do send you a new one and you still want to do this, be sure to lift the positive end of the 4u7 cap; this will reduce or eliminate switch popping. Most people say you have to lift the negative end (I never figured out why they say this) but you can lift either end, it doesn't matter. Just that lifting the positive end will reduce switch popping.
#15
Ah, yea my soldering iron tip is plated or something. I have to be really careful with it and keep it tinned really well, and it probably needs filing right now since it's kinda warped. I've been meaning to get a new iron with an alloy tip for a while but just haven't gotten around to it.

And I'm pretty sure that the cap in question is non-polarized, it says 4.7 NP on the circuit board.