Building the Christine oscillating fuzz PCB

[mthibeau]

I have 3.1v on lug 1, 2 and 3 of the power pot.

- MikeT

Regardless of how the knob is set?

Sorry - tested it again

lug 1 - turned all the way down = 3.5v, all the way up = 5.6v
same for lug 2
lug 3 - turned all the way down = 3.5v, all the way up = 0v

I may have been a little light with my solder connections for my IC socket, I may add a little more to some of them and test again. I took a couple of pictures of the board all built up, would that help?

Thanks again,
MikeT

still getting nothing out of the board... Going through the troubleshooting FAQ and trying everything I can think of. Could I have damaged any components by having the pots backwards and powering it up to 9v?

Re-soldering my IC socket didn't help.

Any other ideas? I get a clean signal still, and the vol, tone and power pots seem to change the volume slightly (tone is quirky - drops out, then back in) when I turn them, but that's it.

- Thanks,
Mike

[Taylor]

Hmm. I went and measured voltages in my Christine, what I had was pretty similar.

You wouldn't have damaged anything with backwards pots. The problem likely has to do with your damaged pads.

The pins of the chip are labeled in the schematic, if you can check the schematic and test with an audio probe what the signal is like at the input and output of each inverter that's in the signal path, it might point to the problem.

I'm a little unclear, when you say you have nothing coming out of the board, does the guitar signal go through the circuit, just without change, or is there no sound when the effect is engaged?

[mthibeau]

Hmm. I went and measured voltages in my Christine, what I had was pretty similar.

You wouldn't have damaged anything with backwards pots. The problem likely has to do with your damaged pads.

The pins of the chip are labeled in the schematic, if you can check the schematic and test with an audio probe what the signal is like at the input and output of each inverter that's in the signal path, it might point to the problem.

I'm a little unclear, when you say you have nothing coming out of the board, does the guitar signal go through the circuit, just without change, or is there no sound when the effect is engaged?

I get a little signal, like a muted guitar sound with some breakup, the tone, vol and power knobs seem to change that sound slightly, but that is it.

Here were the results of my audio probe tests:

Pin 3-4 = nothing
Pin 5-4 = nothing
Pins 7-6 = sound
Pins 8-7 = sound
Pins 9-10 = nothing
Pin 11-12 = nothing
Pins 14-15 = nothing

I tested it with the knobs up full, then again with them all around 50%. No difference.

- Thanks,
MikeT

[Taylor]

Are you sure you're reading the pin numbers correctly? Pin 12 is the output of the last inverter. I don't understand how you can have sound at the output but not at pin 12. Also, pins 7 and 6 are not part of the audio path. I guess there could be some bleed but the fact that you have sound there is pretty strange.

Looking at a chip with the writing visible and the notch or dot at the top, pins are numbered

1 dot/notch 16
2               15
3               14
4               13
5               12
6               11
7               10
8                9

[mthibeau]

Are you sure you're reading the pin numbers correctly? Pin 12 is the output of the last inverter. I don't understand how you can have sound at the output but not at pin 12. Also, pins 7 and 6 are not part of the audio path. I guess there could be some bleed but the fact that you have sound there is pretty strange.

Looking at a chip with the writing visible and the notch or dot at the top, pins are numbered

1 dot/notch 16
2               15
3               14
4               13
5               12
6               11
7               10
8                9

Oops, I had the 2nd row upside down. Still new at this, trying to learn. I am just going to order a new board and try and salvage as many parts off this one I can. I will order it in a week or two after I get paid (spent far to much on DIY stompbox stuff already this month)

- Thanks,
MikeT

[LaceSensor]

ive been asked by someone who might want to buy my build of this if its friendly to active basses,,,anyone know? I dont have one to test...

thanks

[Taylor]

Yes, it will work well and do lots of cool stuff with active bass, but, it will act differently. You won't be able to control the oscillation with your onboard volume/tone controls.

But I've used it on passive bass and it's plenty of fun.

[LaceSensor]

thanks taylor

[jwar]

Hi all! I'm about to start this build and was wondering if anyone had a drilling layout for it?

Also, do you think this will fit properly in a  125B enclosure? I know someone on here stuffed it into a smaller one, but I don't really want to do that. Mammoth has pre-drilled enclosure, but not with the right layout. So my plan is to e-mail them the layout and ask them to drill it for me. I'm out of town, otherwise I'd drill it myself.

What's the success rate with this one by the way? Everyone that build it get it working properly? Taylor is the man!

[Taylor]

In the first post you can see my build in a 1590b, which is smaller than a 125b, and it's pretty tidy - no difficult cramming necessary. So fitting it in a 125b is not a problem (I've built one like that as well) but if it's your first build, leaving yourself extra room can sometimes be a good idea.

[jwar]

In the first post you can see my build in a 1590b, which is smaller than a 125b, and it's pretty tidy - no difficult cramming necessary. So fitting it in a 125b is not a problem (I've built one like that as well) but if it's your first build, leaving yourself extra room can sometimes be a good idea.

Awesome! I actually was hoping you'd chime in. I really dig Iron Ether's look and that pedal looks like one of your regulars. I'll go ahead and order a 1590b then. Do you have a layout by chance I could snag from you? Like I said, I lack the means to drill this puppy where I'm at.

Thanks!

[jwar]

So I spent all day with this bugger and can't get it going. Anyone see any mess ups in my wiring? I know I wired the damn jacks wrong because I started out with a bypassed signal and don't have one now. Any help would be appreciated!

populated board

[Taylor]

Check these out:

http://www.diystompboxes.com/pedals/debug.html
http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[jwar]

Thank you Taylor! Looks like I have some reading to do!

[Vince_b]

So I spent all day with this bugger and can't get it going. Anyone see any mess ups in my wiring? I know I wired the damn jacks wrong because I started out with a bypassed signal and don't have one now. Any help would be appreciated!

The wiring of the input jack looks wrong. You have connected the input to the "ground" tab and the ground to the "switching" tab. I can't see the output jack, but it might be wrong also.
You should use a multimeter to test how to connect those jacks.

[jwar]

So I got everything wired up again, the correct way now because I'm getting a bypassed tone when I wasn't before. Still no LED, no effect either. I check all the paths with a multimeter and I believe it's the darn 3dpt switch! I think I may have just had a bad one. I'm going to try it with a new one in a bit. The reason I'm thinking it's the 3dpt is because I get the LED to come on with my multimeter touching different points, but get nothing on all the far right pins. So it seems that it's not properly flowing through the switch. I've triple checked the way I wired it too. So that's my next trouble shooting idea.

I'll get it going, I'm sure. Just gotta find that bug! Those links you posted really help btw Taylor! Some excellent ideas in there.

Oh and I just realized I suck at drilling, so this one is going in a blem box. hahaha.

[petey twofinger]

switches can fail if you hold the iron on them too long .

i have been sanding the terminals a lil , pre-tinning the wires , then adding a tiny ammount of flux to the terminal after threading the wire thru . its important to remove that flux !

sounds like a hassle but i have also ruined my share of parts from overheating .

[tiges_ tendres]

Don't assume it's your switch.  It sounds like a grounding problem to me.

Those jacks you are using are not standard switchcrafts so  they may have a different lug orientation.

[jwar]

That's a thought. I actually had considered that as well. I have since rewired the jacks and it bypasses fine. But there still could be a grounding issue. I'm going to double check that later.

Another thought I had was the diode. Does the orientation of the diode matter at all? If so, I may have put my the wrong way. My first instinct was a backward IC, which I've done before, but it's the correct way now.


At any rate, I'll continue to trouble shoot this guy! I can't wait to have it up and running! It won't be long. I usually have issues with my builds and they end up being something completely ridiculous that I just overlooked. Like a disconnected wire or a bad solder joint or the backwards IC.

Thanks for all the help guys!!

[Vince_b]

The orientation of the diode is important. It might not be the cause of your problem in this particular case but should check to be sure that you put it the right way.