News:

Forum may be experiencing issues.

Main Menu

Finished: Advice on modding a Crybaby: Wiring help needed

Started by TNblueshawk, February 28, 2024, 10:58:14 PM

Previous topic - Next topic

TNblueshawk

So, my new neighbor who moved in next door in a rental happens to be the guitar tech for Derek Trucks and Susan Tedeschi. No really he is. He would like a 9v PS with the battery option and an LED, basically like we build them now put into an old wah. Ok, if new easy peasy. However, this is not MY old wah so I'm not jumping in guns a blazin'. He thinks it's vintage and while it's old I have no idea if it has mojo but to him it does. So with that in mind.....

I've poked around on the webz and one thing that pops up is that once modified for the PS it becomes noisy. Some other folks said theirs was not. Who knows with this one.

Question 1: Can I dive in and wire for TB like all the others, stereo jack for in the input of course for battery use, LED, etc... or is there something about how these things were wired that would not allow for what appears to be a straightforward fix?

Question 2: If I do wire for TB do I have to cut the buffer trace/get rid of the buffer in some way? I read this over at Stinkfoot.

I don't intend to mess with the PCB per se if I can help it. I'll just strip the existing old wire and lengthen with the new wire not disturbing the PCB at all.

I'm wide open to some thoughts and potential pitfalls to bringing this puppy up to modern times.











John

lars

#1
Do not mod the case or anything! Simply get a 9V battery clip and a female DC barrel plug to make a "dongle" similar to this:
https://www.taydaelectronics.com/9v-9-volt-battery-clip-connector-with-barrel-jack-plug.html
You can easy create a space for the thin wires to fit through by putting a spacer washer in between the bottom plate screw and the case. This mod will work to be able to plug into a modern power supply, but you will not be altering the originality of the pedal in any way.

*edit* There is one reversible mod I would highly recommend:  carefully desolder one leg of that 33K resistor at the top of the PCB to take it out of the circuit. Guaranteed the wah will sound better without it. The original Thomas organ patent didn't have it. I know it's the "Q" resistor, but in my experience I've found it to be the "poo" resistor; some wahs even put a potentiometer there, so you can adjust the levels of poo! Leave it out.

Bret608

I'm only seeing two transistors there, so I don't think there's a buffer to remove. For the TB mod, take a look at Stinkfoot's site. He tells how to do it on all the various Dunlop versions, so the oldest wired one would probably be translatable to this Thomas Organ one.

I never know that about the Q resistor. I upped it to 47k on the old Dunlop I have and it was an improvement, but I may try taking it out to see what happens.

TNblueshawk

#3
Quote from: Bret608 on February 29, 2024, 01:30:37 PM
I'm only seeing two transistors there, so I don't think there's a buffer to remove. For the TB mod, take a look at Stinkfoot's site. He tells how to do it on all the various Dunlop versions, so the oldest wired one would probably be translatable to this Thomas Organ one.

I never know that about the Q resistor. I upped it to 47k on the old Dunlop I have and it was an improvement, but I may try taking it out to see what happens.

Thanks Bret. I found the exact board off a link he supplied that had good instructions.

I'm not messing with the PCB itself as it's not mine. I just hope I can get it working with a PS and an LED without killing the pedal!
John

TNblueshawk

Quote from: lars on February 29, 2024, 12:54:27 AM
Do not mod the case or anything! Simply get a 9V battery clip and a female DC barrel plug to make a "dongle" similar to this:
https://www.taydaelectronics.com/9v-9-volt-battery-clip-connector-with-barrel-jack-plug.html
You can easy create a space for the thin wires to fit through by putting a spacer washer in between the bottom plate screw and the case. This mod will work to be able to plug into a modern power supply, but you will not be altering the originality of the pedal in any way.

*edit* There is one reversible mod I would highly recommend:  carefully desolder one leg of that 33K resistor at the top of the PCB to take it out of the circuit. Guaranteed the wah will sound better without it. The original Thomas organ patent didn't have it. I know it's the "Q" resistor, but in my experience I've found it to be the "poo" resistor; some wahs even put a potentiometer there, so you can adjust the levels of poo! Leave it out.

Lars, great advice on the 33k. I would have to ask him about that one but it is easy enough. I could socket it to in case he didn't like it down the road.

As far as altering the case I plan to first not drill holes, wire up the PS and LED hanging loose and then get with him and ask him one more time if he is sure. He never plans to sell it. He has had it a long time and he is young. At the end of the day I'll go with what he wants to do.

But I hear what you mean and say about not doing irreversible damage to a vintage pedal.
John

TNblueshawk

#5
Ok, so I sure could use a second opinion and insight on this. First. I went to Stinkfoot and sure enough found my exact PCB which was not on his site but he links you to another site for pre 1990 Wahs. On the PCB drawing below I seem to have a discrepancy on the terminals. I've gone over this in my head multiple times but again it's not my Wah so I'm trying to get this right out of the gate vs trial and error.

So if we start at the top of the Wah/PCB you have 6 terminals on the right descending.
1- PCB output?
2- PCB input?
3- PCB ground?
4?
5- Ground second one?
6- 9V

So if you will notice I have the battery hooked up to the last 2 terminals in the pics above. The pedal works like this so I'm thinking the 9v is the last one. There is also a red wire going to the input jack so I'm thinking good that's it. But if you look at the wiring diagram below off the website it has the opposite it appears with the ground as terminal 6 and the 9v as terminal 5. What gives?

I'm adding an LED thus the 3PDT. Also a pic below shows how I'm wiring the stomp switch.

Any thoughts on how to wire this one up?





John

Funkasaurus

Hear me out on this, what if you abandon the idea of modding the wah itself?  I used to buy used Crybabies of all sorts back when they were $20 and less on eBay and do all sorts of silly things with them.  If you change out the old switch to a 3PDT, chances are you are going to need to shave down the rubber bumpers in the front to be able to reliably actuate the new switch (assuming they are still attached).  The standard wah switches are taller than a 3PDT, and it turns into a whole balancing act once you start changing out the parts.

With a choice vintage unit like this I would try to convince them to just go with a little bypass loop pedal for the wah instead.  I did one of these for my friend's Morley wah, because he has bigger feet and had a hard time consistently catching the switch on the Morley on a dark stage.  All you would need would be a box, 1/4" and DC jacks, LED, and your switching setup.  You could just put a 3PDT in there or you could get fancy and do soft touch relay switching so it would be easy to pop on and off.  That is the route I would try to convince them to go with it.

jimilee

There's a guy in town that used to mod them with a momentary switch on the treadle so you don't have to stomp it, it just works.


Sent from my iPhone using Tapatalk
Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

lars

Now that I've looked over the pictures a bit more, I noticed the two carbon comp 470K resistors have been swapped out for carbon film, so I wouldn't worry too much about modding the pcb in any way, it's already been worked on.
As for the LED, where are you planning to put one? LED's on wahs are really only effective if you can somehow place it on top of the foot control, like the old PAX "Pedal Number One". Otherwise it just gets lost at most viewing angles. I guess something in the heel of the case would be a fairly visible option as well, but would only look cool if it was an amp jewel like on the old 70's Morley wahs.

TNblueshawk

#9
Quote from: lars on March 01, 2024, 10:40:07 PM
Now that I've looked over the pictures a bit more, I noticed the two carbon comp 470K resistors have been swapped out for carbon film, so I wouldn't worry too much about modding the pcb in any way, it's already been worked on.
As for the LED, where are you planning to put one? LED's on wahs are really only effective if you can somehow place it on top of the foot control, like the old PAX "Pedal Number One". Otherwise it just gets lost at most viewing angles. I guess something in the heel of the case would be a fairly visible option as well, but would only look cool if it was an amp jewel like on the old 70's Morley wahs.

Lars, I was going to put it at the heel. I did a couple others like that. Yeah, I wish I had some of my old jewel lights but I used them up on pedals!
John

gordo

The only reason I started building amps was because I chopped up a 77 Marshall JMP 50 Master Volume.  I know, it would be worth a fortune and although it sounds better with it's Dan Torres mods it's basically worthless.  Still, this is one kickin 50 with tube fx loop, switchable master volumes, and extra gain stage.

Pedals are not so much.  I would ALWAYS recommend that a pedal of this vintage not be modded, but truth be told he's not going to retire on it so if he's good with violating it.  Have at it.

Cool gig, and if he's comfortable working with you it would be cool to feed the band some pedals too.  I got an overdrive, when I still had Laffing Dog Musical Instruments, over to Mark Knopfler and Charlie Sexton when Knopfler was supporting Bob Dylan thru their light guy.
Gordy Power
How loud is too loud?  What?

TNblueshawk

Quote from: gordo on March 02, 2024, 12:03:54 AM
The only reason I started building amps was because I chopped up a 77 Marshall JMP 50 Master Volume.  I know, it would be worth a fortune and although it sounds better with it's Dan Torres mods it's basically worthless.  Still, this is one kickin 50 with tube fx loop, switchable master volumes, and extra gain stage.

Pedals are not so much.  I would ALWAYS recommend that a pedal of this vintage not be modded, but truth be told he's not going to retire on it so if he's good with violating it.  Have at it.

Cool gig, and if he's comfortable working with you it would be cool to feed the band some pedals too.  I got an overdrive, when I still had Laffing Dog Musical Instruments, over to Mark Knopfler and Charlie Sexton when Knopfler was supporting Bob Dylan thru their light guy.

I'm guessing he is not a purist as such but I would have to have a deeper convo. I'm just getting to know him. Like I said I won't drill holes but first I want to see if I can get it working as he wants and then I will talk to him. His call at the end of the day.

Any thoughts on the wiring Gordo?
John

lars

I wonder if there are any clear isolation washers for 1/4" jacks? That could be another solution for adding LED lighting to an older pedal without having to do any mods. They already do this type of LED lighting for stomp switches.

TNblueshawk

Quote from: lars on March 03, 2024, 01:50:50 PM
I wonder if there are any clear isolation washers for 1/4" jacks? That could be another solution for adding LED lighting to an older pedal without having to do any mods. They already do this type of LED lighting for stomp switches.

Dude I would buy those just for own pedals! I have never seen them or heard of them. I thought I saw a build not long ago with the stomp lit up but no way can I remember where.
John

TNblueshawk

Ok it's done. Look away purists. You will find this offensive  :o

I did reconfirm he wanted done with what he said he wanted done so it is done how he said he wanted it done. I wanted to put the LED in the heel but no worky with the battery there.

I've got a switch pop I'd like to get rid of and the 1m on the input didn't affect it at all. If anyone has an idea I'm all ears.





John