#1
Yeah, as the title suggests, my Boss CS-3 is ****ed, and has been for a while.

It gives me the same crackly crap on bypass and with the effect on, with no volume boost or noticeable change in sound. I can't see any obvious connection problems or burning inside, so does anyone have any ideas?

I'll probably end up using the enclosure for something else, if there's nothing I can do, but I'd like to salvage the £45 unit :\
#2
you checked the pots/ switch with a multimetre?
Quote by Deliriumbassist
Antisocial Behaviour Order. A chav's equivalent of GCSEs.
#4
hmm

all the other componnents?

it could be a loose connection somewhere or a grounding issue?

your probably more knowledge able of it though :P
Quote by Deliriumbassist
Antisocial Behaviour Order. A chav's equivalent of GCSEs.
#5
Quote by rancidryan
hmm

all the other componnents?

it could be a loose connection somewhere or a grounding issue?

your probably more knowledge able of it though :P


Haha, man, I have no idea what's going on with electronics stuff.

I've just tested all of the components on the main PCB, and they're all fine too :\
#6
check all the links then and can you post a pic of the guts?
Quote by Deliriumbassist
Antisocial Behaviour Order. A chav's equivalent of GCSEs.
#7
This is what I've got:





It's weird, because I get sound when I play, but it's layered with fuzz. If I turn my amp up loud enough, I can hear the guitar coming through clearly, but the fuzz is significantly louder.
#8
I'm trying to resurrect this now... and I have a query. If this is the schematic, should I be seeing 9v from the battery positive to the end of IC4?



Edit: Scrap that. I'm seeing ~8.5V across all of them.

Also, should I be seeing the same voltage across Q1? I'm getting exactly the same results (very quiet guitar signal and loads of noise) in bypass and active, so I'm wondering if something is wrong in the input buffer. I could be barking up the wrong tree though...

I'm getting ~5.9V after IC1 and Q1 had bent legs, so I'm going to try replacing those two components first.

Edit2: I've just replaced R2 and R28, because I had some 10K resistors hanging around, but it's made no difference. The next step is to go ahead with replacing the other components (C1, C3, IC1) and see if I get 4.5V. If none of that works, I'll try replacing Q1, IC2, IC4, Q2 and Q3. The parts are cheap and on order, which is nice.
#9
Most likely the transistor flip flop bypass switching has gone wrong. This can be confirmed with voltage and resistance measurements if the two FETs doing the switching. Q4 and Q5
Q2 and Q3 could also be not working but leave them for now.
#10
Quote by kurtlives91
Most likely the transistor flip flop bypass switching has gone wrong. This can be confirmed with voltage and resistance measurements if the two FETs doing the switching. Q4 and Q5
Q2 and Q3 could also be not working but leave them for now.


Thanks, man. Is there a way to check them in situ, but without power? I've already removed C1 and C3 in preparation for the new parts :x
#11
Measure the resistance from the drain to source on both of them. Do this with the pedal bypassed and engaged.

Just telling you now there is a very good chance those passive parts you are replacing are fine. Passive parts don't just fail.
#12
Quote by kurtlives91
Measure the resistance from the drain to source on both of them. Do this with the pedal bypassed and engaged.

Just telling you now there is a very good chance those passive parts you are replacing are fine. Passive parts don't just fail.


Ah, okay. They were dirt cheap, so I won't be too worried if they don't fix it. I was following some tips for fixing one of these if it's had the wrong power supply connected... which is what I might have done, but it was so long ago now.
#14
Sweet, the parts came today. I have replacements for D1, C1, C3, IC1, IC2, IC4, Q2 and Q3. I've also ordered replacements for Q4 and Q5, just in case.

I'll give a heads up when I've got some results...
#16
Quote by kurtlives91
This


These are the results that I'm getting:

Bypass:
Q4 - 1063k and 560k
Q5 - 320k and 310k

Engaged:
Q4 - 1062k and 335k
Q5 - 1594k and 2000+k

Unless I've measured them wrong, doesn't that mean they're dead? I've just read somewhere that I should expect 10k from source to drain...

Edit: I've replaced IC1 and it's now working. The only issue now is that the sustain control introduces a clicking noise, which speeds up as you turn the pot. All of the other controls work fine.
#18
Quote by kurtlives91
Read from the drain to source on both Q4 and Q5. Do this with both the pedal bypassed and engaged.

Not sure what you are measuring.


Neither am I, really :\ Electronics isn't really my field. They must be okay if it's working now, right?

Sorry for being a 'tard.


Edit: I've just put it back together and the sustain control works fine now, without the heinous clicking. The pedal is noisy in general though :\

Thank you for your help!