crybaby mods...I messed up...

Started by Hal, October 08, 2004, 08:55:42 PM

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Hal

please help :-\

ok looking at this:
http://www.geocities.com/j4_student/crybaby95.gif
and this:
http://homepage.ntlworld.com/s.castledine/greenfuz/wah.html
specifcally, the line in the second page that said "Lifting the earth connection of the 4.7µF capacitor will cancel the wah effect and leave you with a volume pedal."

OK so the idea was the keep the pedal always "on."  So i cut the three wires from the switch, soldered the blues and the green together, and left the purple hanging.  I then pulled the 4.7 uf cap off the board, soldered the posative lead to a wire, the negative lead to the switch, and a wire from the switch to ground.

The idea was that i could use the switch to change the pedal from wah to volume.  I can't find anything flawed in the theory, as long as Stuart Castledine's statement was correct.  I'm 99.9% sure all my connections are good - I checked them all at least once....

argh.  I'm stumped.  Any ideas?

edit: when i say it doesn't work, I mean exactly that.  Nothing happens.  At all.

Mike Burgundy

from those pics:
green is the wire from input jack to circuit in and via switch out ("bypass")
purple is the wire from switch to out
blue is output circuit, to purple, with the switch in the right state ("on").

Okay,
blue and green together, taken from the switch, should hardwire the pedal iin output-to-input-mode. Won't work - at all - the circuits input and output are connected, but nothing goes to the output jack. Purple!
Purple hanging? You mean leave it in place, or...?
Try wiring purple and blue together - purple is the line to the pedals output, blue is the circuits output. Leave green as wired originally, this is your circuit input. Actually, you could disconnect this entirely, as long as there's a connection between the input jack and circuit in, which apparently is the case.
You got the wiring mixed up - which is something that happens to all of us.
Think about the circuit as a whole in terms of signal flow, "from here-to her-goes to..." It helps, really. I have to check at times too, so don't feel bad.

Hal

DOH!

wow, without thinking i just thought "ok in one position green shorts to purple, bypassing, and in the other position, green goes to blue - blue leads to the rest of the circuit.  I'm still having trouble tracing the buffered input.  

so blue is FROM effect, green is TO effect, and purple is TO output.

This still confuses the crap outa me.  The signal hits the jack, goes to the input buffer, and is "wahed" In switch position 1, when green connects to blue, cricuit out goes to in, and... ?

in switch position 2, to effect goes to to output, green to purple, shorts in and out, and bypasses.  I'm still having trouble thinking of it any other way.  I guess this is wrong.  

I understand what you're explaining, but don't see how it works, still...that is, in terms of the switch...

UNLESS I have the switch's pinout wrong.  Now its all falling into place....Im gunna go see if i can fix it. This is kinda sream of consiousness post.  Thanks :-D

Mike Burgundy

It's easy. This is not a true bypass switch, think of it's action this way:
When "on" purple is connected to the blue wire.  Purple is the "switching" connector, and alternates between green and blue.
The input jack is connected to a) the circuit input AND at the same time b) the green wire. The green wire is connected to nothing at all at the other end because of switch position.
The output jack is connected (via blue/purple) to the circuit out.
When "off"
The input jack is still connected to the circuit and the green wire. The circuit is fully functional, BUT is no longer connected to the output!
Since the purple wire is switched to the green wire, the output jack is now tied to the input jack directly, with the circuit dangling from the lot (and acting as a passive filter, too)

Look at this diagram, should enlighten you a fair bit:
http://www.geofex.com/Article_Folders/bypass/bpdiag4.gif

Hal

GOT IT!

The reason that i thought of the circuit backwards is that the green wire is on the outside of the switch - its exactly like in that picture.  So I thought that in one position, the green connected to blue, and in the other position, green to purple.  I didn't even test that, until now - just assumed it, from looking.

That'll teach me!

Thanks so much for your help, and the mod is awesome, just how I wanted it :-D.  I may lose a little tone in bypass, but the functionality is excellent.  Maybe I'll put in a better buffer at some point.

ESPm2M

If you install a 3PDT you can have true bypass switching for the whole modded unit and have an LED indicator to boot.

David

Quote from: HalGOT IT!

The reason that i thought of the circuit backwards is that the green wire is on the outside of the switch - its exactly like in that picture.  So I thought that in one position, the green connected to blue, and in the other position, green to purple.  I didn't even test that, until now - just assumed it, from looking.

That'll teach me!

Thanks so much for your help, and the mod is awesome, just how I wanted it :-D.  I may lose a little tone in bypass, but the functionality is excellent.  Maybe I'll put in a better buffer at some point.

Hal:

Your wah/volume selector mod works, then?  I've been thinking about doing this.

Do you have a buffer on the input and/or output of your wah?  I was thinking that if you leave the wah in your signal path all the time, you wouldn't need bypass capability at all.

Hal

Quote from: David

Hal:

Your wah/volume selector mod works, then?  I've been thinking about doing this.

Do you have a buffer on the input and/or output of your wah?  I was thinking that if you leave the wah in your signal path all the time, you wouldn't need bypass capability at all.

Yup!  Works nicely - exacly what I was looking for.  After my silly mishap, its a fairly easy mod to make.  I put the electro right on the switch, so I didn't have to deal with mouning it somewhere....

The buffer is still on the input, just as it always was.  I didn't do any major circuit mods (yet).  Many people complain about the fidelity of the crybaby buffer, but I really don't think its too bad.  Maybe if I had better amps/guitars/cables I'd notice it more, but it sounds fine to me :-D

ESPm2M - the point of this was that I don't need bypass anymore.  When its in "voulme mode" the signal is clean, no wah, and at unity volume at the toe.  I can also rock back the volume if I want, though.  Or swell :-D :-D

kinda OT: didn't feal like going down to the basement to solder those last 2 wires together...did you know that a normal lighter can melt the solder?

David

So you followed Stuart's schematic for the Jen wah/volume, then?  IIRC, that had a DPDT switch arrangement.  Did you happen to try opening the ground connection for the 4.7 uF cap on a CryBaby?  I would think that would just take a SPST switch.

Hal

Quote from: DavidSo you followed Stuart's schematic for the Jen wah/volume, then?  IIRC, that had a DPDT switch arrangement.  Did you happen to try opening the ground connection for the 4.7 uF cap on a CryBaby?  I would think that would just take a SPST switch.

It would...I used the toe switch from my crybaby, a spdt, though.  I only used 2 poles of the switch....to break the ground connection, or to connect it.  There is no bypass - the pedal is now either wah or volume. But if you leave it in the toe position, its just as good as bypass....

David

Quote from: Hal
Quote from: DavidSo you followed Stuart's schematic for the Jen wah/volume, then?  IIRC, that had a DPDT switch arrangement.  Did you happen to try opening the ground connection for the 4.7 uF cap on a CryBaby?  I would think that would just take a SPST switch.

It would...I used the toe switch from my crybaby, a spdt, though.  I only used 2 poles of the switch....to break the ground connection, or to connect it.  There is no bypass - the pedal is now either wah or volume. But if you leave it in the toe position, its just as good as bypass....

EXCELLENT!!!!!   :mrgreen:  :twisted:  :twisted:

This is just what I was hoping you would say!  Yee-HAH!
I may have some wah-related news of my own to report in the near future...  stay tuned!

bass_econo

Ok, I know this has been asked about a zillion times, but...

I did this mod on my friends wah, tonight.  I added a spdt to the side of the pedal to changed from wah to volume.  I also did the wah/woh mod.  The problem is that the volume does not go completely off.  I have tried adjusting the rocker, but it still only goes so low.  Then of course the wah is limited.  

Has anyone found a fix for this or am I out of luck?

TIA!
James

Hal

yup  - mine has the same problem.  I don't really care too much though, I plan on using it for swells, or solo "boost," not for "kill."  I have my guitar's knob for "kill."

ESPm2M

Quote from: bass_econoOk, I know this has been asked about a zillion times, but...

I did this mod on my friends wah, tonight.  I added a spdt to the side of the pedal to changed from wah to volume.  I also did the wah/woh mod.  The problem is that the volume does not go completely off.  I have tried adjusting the rocker, but it still only goes so low.  Then of course the wah is limited.  

Has anyone found a fix for this or am I out of luck?

TIA!
James


I also did the bare-bones volume mod using a SPST switch with the same behavior.  However, it was not a surprise because I was aware of the limited physical sweep of the pedal/pot.  I believe that the Jen Wah/Volume schematic has a certain portion of the circuit designed to improve (or eliminate?) this issue.  I will perf board it and install it when I am home next and let you know how it works out (it could be several weeks - I'm at college).

btw, find my post in this thread to read about my wah project...
http://diystompboxes.com/sboxforum/viewtopic.php?t=25898&highlight=