Help with Dirtbaby

[Melissadrive]

Hey Guys,
I need some help with my dirtbaby build. Had a lot of problems solved some, but more seem to pop up. At the moment I can get the delay to work intermittently but the chorus/vibrato is non existent. If the feedback pot is in anything other than the minimum position the feedback goes out of control and distorts as though it was maxed out. Sometimes just touching the pots just cuts the signal out. Here is a link to photos of the board, both front and back as well as pinout readings for the ICs.

IC 1 - 7.4, 8.05, 3.84, 3.84, 0, 3.84, 0, 3.72. IC 2 - 4.97, 2.48, 2.47, 0, 0, 2.48, 0, 2.48, 2.74, 2.48, 2,47, 2.48, 0.38, 2.48, 0.75, 2.48. IC 3 - 7.37, 7.94, 3.83, 0.61, 0, 3.83, 0, 3.83. IC 4 - 1.44, 8.05, 2.64, 3.83, 2.57, 3.88, 0, 3.83.

Images:
http://imageshack.com/a/img921/2491/xxbESe.jpg
http://imageshack.com/a/img923/9651/ukCoNR.jpg
http://imageshack.com/a/img921/1416/AdqQSA.jpg
http://imageshack.com/a/img921/5076/PISYD4.jpg
http://imageshack.com/a/img921/9799/9AVH5o.jpg
http://imageshack.com/a/img924/3945/XlYKg2.jpg
http://imageshack.com/a/img923/7711/LeATxM.jpg
http://imageshack.com/a/img921/1576/YtEXRX.jpg

Thanks in advance for the help guys, sorry if I've missed something obvious but I am stumped. Please let me know if you need some more stuff to go on. Have tried replacing some of the pots, all the pots I'm using are brand new from mouser. I can record and upload an audio file of the problem if it would help.

[m-Kresol]

Hi there,

I hate to say this and please don't get this in the wrong way, but it seems to me that you violated the board pretty badly. I can see several points were the solder mask is scratched off to the blank copper. I assume you used a blade to ensure there's no solder bridges somewhere, but you might just have cut a trace will doing so. I would propose to use a multimeter in continuity setting to check with the schematic if the parts that are supposed to be linked are indeed. It's tedious for sure, but no other way of knowing.

Also some of your solder joints look dull and could need a reflow, maybe it's a cold solder joint somewhere.

About the voltages: I see lots of correct values, but for the wrong pins. How did you measure them? the way they are numbered is to start with pin 1, which is marked by a small dot or is in below the half-circle cutout marking. then go counter clockwise from there. Please remeasure those voltages so they are in the correct order.

Good luck

[jtaormina]

Use a little isopropyl alcohol and a q-tip and clean some of the flux off then evaluate the solder pads again. It does look a little heavy handed in a few spots.

[Melissadrive]

Thanks for the help guys, yeh. The board is a bit mangled, I did use a blade to scratch around the tracks. I'll try the isopropyl and recheck the pin values tomorrow and get back to you.
Thanks again for the help, I am fairly new to this so it is all a learning experience

[Melissadrive]

Sorry for the delay.

I've cleaned the PCB with some isopropyl alcohol and re-flowed the solder. Still having the issue. It seems that the 'level' and 'feedback' pots are causing some problems. Just touching the pot can send the thing crazy even with the feedback turned down. Might try with a new set of pots and see if that works.

The voltages (corrected, thanks m-Kresol) IC 1 2.88, 3.38, 2.66, 0, 8.01, 3.95, 3.65, 2.91  IC 2 4.95, 2.47, 0,0,0, 2.47, 1.68, 3.82, 2.54, 0,2.45,2.47, 2.47, 2.48, 2.47, 2.65
IC 3 3.45 (fluctuates between 3.45 and 4.5), 3.81, 3.93, 0, 8.03, 3.63, 4.01, 3. 83  IC 4 3.88, 3.82, 1.92, 0, 8.00, 3.80, 3.78, 3.76

Uploaded cleaned photos as well.
http://imageshack.com/a/img921/8792/JsOl0N.jpg
http://imageshack.com/a/img922/6416/iLmCOS.jpg
http://imageshack.com/a/img924/3917/BOG3cR.jpg
http://imageshack.com/a/img922/2504/0gW3Hh.jpg

Thanks again for the help. Getting to the point where I might just order a new pcb. But really want to get this to work. So close

[m-Kresol]

the soldering looks definetely better now; I've marked a few things on your pic that you should recheck. Marked in RED: make sure that the solder residues between the pads does not short them. For the 9V/GND pads up top that's clearly not the case atm, but could cause issues down the road.
marked in GREEN: use a multimeter to make sure these pads are not connected (R1 and R5).

Pic is here.

Voltages still look off to me. I'm not sure you read them correctly, so just to be sure, this is the numbering scheme. I say this because you got your supply voltage on IC1 on pin 5 instead of 8 if you did it right. that would be a bad thing
on your PT2399 (IC2) recheck Pin 10 (the one that measured 0V on your numbering).

So, I guess you already checked all your component values. Recheck them again please. When voltages are off, that's one of the main reasons.

For future reference, socket Pt2399 chips for several reasons:
*) those are digital chips and thus are a bit more sensitive (heat, overvoltage, ESD)
*) they are also prone to sounding bad and you might have to try a few to find one that suits you
*) --> pain to desolder a 16 pin chip!

Don't just get a new board now! I think we can still manage it. maybe not today, but somewhere down the road. This is an "expert" level project for sure where many things can go wrong.
Based on the pictures and voltages, I assume you're new to this, so I'd suggest maybe starting with a simpler project to get your feet wet before tackling a delay. No offense.

Cheers