Author Topic: need help DEBUGGING this OCD clone plz!!!!!  (Read 12730 times)


need help DEBUGGING this OCD clone plz!!!!!
« on: March 10, 2014, 07:44:18 PM »
I cannot for the life of me get a build of *VERSION 1 to work, I'd really appreciate anyone's input on this. I've tested most of the components on the whole board, replaced the IC, reflowed all the solder joints, checked for solder bridges, etc. Only get sound in bypass, can't get any sound with the pedal on, sometimes just a popping sound. Thanks!

Here's the IC voltages...

PIN #1: 1.418, PIN #2: 1.25, PIN #3: 1.03, PIN #4: 0.1,
PIN #5: 9.28, PIN #6: 1.423 PIN #7:1.09, PIN #8: 1.286

Hoping this reveals something. Maybe PIN #4 needs to be resoldered?

(schematic here...  :icon_eek: ???
« Last Edit: March 10, 2014, 10:35:20 PM by czech »


Re: need help DEBUGGING this OCD clone plz!!!!!
« Reply #1 on: March 10, 2014, 08:07:02 PM »
Hi, I just finish a pretty tough pedal with too many wires inside and couldn't get to work till right now. 

I am only going to give you a bit of advice on how I personally tackle troubleshooting.

Get your DMM and site on continuity and check every possible point that should not be touching. Especially with ground. I realised that the tip of one of the jack was touching the side of a switch which underneath the wires was hard to see.
Then get yourself a probe. I just use the output cable from my (beavis board inspired) prototyping board to see where the signal is going and where it is stoping. By just following the schematic. If none of these work. I would turn to either a mistake in the wiring( which I guess you've already checked) or faulty components.

One of the very hard issues to find but which might happened with plastic jack is that the tip touches the ground inside it. It is pretty uncommon but can still happen

Anyway good luck with your board and bonne nuit
Don't know what to do with a paritculare transistor? Check this website where stompbox pedals are listed by what transistors they use


Re: need help DEBUGGING this OCD clone plz!!!!!
« Reply #2 on: March 11, 2014, 11:00:20 AM »
czech, hello and welcome to the forum.

it's nice to see you're using bits of vero on your pots. not many do. but, you must not have any exposed wires running about yr insides, it will case problems. insulate all of those led/resistor wires.

the schematic you linked to is not a schematic, it is a layout. the layout is for the building, but the circuit diagram is for the telling of what voltage will appear on what part. if you can find the circuit, PLEASE, post it here. many of us don't/won't try and read vero. and, not to be picky, but that page shows a "version 1" and a "V1". it doesn't matter, but we need to be accurate.

pin numbering. your ic voltages are off, and the ones that are "right" appear in the "wrong" places. from your first image: pin1 of the IC is top left, as indicated by the circle indent on the IC. count 1-4 down the left side, then pin 5 is bottom right. pins 5-8 from bottom to top. so, you should have "0V" on pin 4, and "+V" (9V? 8.5V? 10.2V? it will vary with battery) on pin 8, not pin 5. and, pin 3 is connected to a 470k resistor, connected to a Vref divider. this means you should have close to 1/2 of your "V+" on pin 3. find out why you don't have V/2 along these couple parts, you'll be well on the way to fixxe.

what type # mosfets are you using?

good luck. let us know if you have more trubble.
wait: up, higher.


Re: need help DEBUGGING this OCD clone plz!!!!!
« Reply #3 on: January 24, 2015, 01:48:00 AM »
I have nothing constructive to add, but I feel your pain. I'm also trying to debug an OCD clone and it's driving me nuts.