Supercell Overdrive - No Signal

Started by andresl7, September 15, 2014, 05:27:10 PM

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andresl7

Hi. I bought the supercell overdrive pedal from mammoth electronics and this is my first built.  However after I finished building the pedal circuit i tried it and when i stepped onto the footswitch the led came on but no sound was going thru , not even the clean or overdriven signal just silence. I tried raising the levels on the pots but nothing.
So , basically I had it checked by an electrician and he told me that I hooked it up correctly and that every element was working fine , the solder was well made and the parts ( including pots ) were not damaged. He couldnt really understand why the pedal was not working because it was hooked exactly the way that was shown on the build documents provided in your website, but he did say that the only reason he could come up with to explain that malfunction would be a defective Integrated Circuit. Any suggestions as to why im not getting any sound out of the pedal ? Thanks for the help guys, im a begginer in this and I would like to learn from your experience. thanks

J0K3RX

#1
Well, I am going to point you in the right direction... This is the preferred method when asking for assistance in trouble shooting.
http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

Now, I don't know that an electrician is the best resource to help trouble shoot but if that is all you have and he is good with this type of circuitry then it's just as well.. There are the obvious things like "is the IC in correctly as in not backwards?" and "is the IC good" as your friend pointed out already. You should be able to determine that by getting some voltage readings... Is your foot switch wired correctly? You can check that by totally eliminating it and run the board direct... Double check the polarity on everything etc..
Doesn't matter what you did to get it... If it sounds good, then it is good!

andresl7

Oh my bad. Im sorry , I should have posted the correct information. This is the build schematic I used and I did follow that build exactly the way it is shown on this document.

I FOLLOWED THE 3PDT wiring , which is the 2 page of that Document:

https://dl.dropboxusercontent.com/u/16935243/Build%20Docs/00321%20-%200003MAM%20-%20Mammoth%20Electronics%20-%20Instruction%20Manual%20-%20Super%20Cell%20Overdrive%2009.pdf

I didnt do any type of MODS or nothing like that and I checked that everything was properly soldered into the circuit before trying it.
When I press The footswitch , the Led comes on which I believe means that the footswitch is working properly.
The main issue like i said is just that it wont make any type of sound , there is no signal when I plug in my guitar and press the footswitch. No clean signal nor overdriven signal.
I will try to see if that IC is defective , because we checked and it was properly hooked into the PCB.
The rest of the components , according to my friend, seemed to be working properly and they were hooked up in the correct direction in terms of polarity.

duck_arse

generally speaking, if the led comes on it indicates nowt but that the led is wired correctly. can we see some photos of what you have built? nice and clear (but please not huge, some of us use wet string to connect the interwebs), both sides of the board, and the off board stuff.

and hello and welcome.
don't make me draw another line.

andresl7

Yes, thank you for welcoming me here. These are the pics of the project, one of the wires from one of the jacks got loose so you may see it disconnected from the circuit, but that only happened minutes ago when i was trying to move it so i will solder that back up. Aside from that you can see all the connections and components on the circuit






If you need anything else, just let me know. ill be glad to provide you with more photos or information :) thanks



andresl7

if you need closer pictures or different pictures just let me know and i will Take them. thanks guys for taking the time to help me. I know this is basic stuff so I really appreciate that youre taking the time to help

duck_arse

nearly. we need to be able to see the details, so we can point to your board and say "that resistor is 10k instead of 1M" or "that solder is dry/bad" and like that. so, photos of about that size, but just board filling the frame. scout some of the other debugg threads to see what we mean.

do you own a multimeter?
don't make me draw another line.

mth5044

I'm sure it's an illusion, but in the first picture it doesn't look like the 3PDT is soldered in at all.

As outlined in the link from JOK3RX, could you take voltages, especially of the IC? A signal tracer would also be useful and you can find the information on this site and it's wiki for building one. A close up picture of the top and bottom of the board would be helpful. Are you getting clean sound when the effect is bypassed? You mention no clean or overdrive, but does that mean when the effect is on or no sound at all in bypass or engaged?

andresl7

Oh Ok , ill take the closer pictures and send that to you. I dont own a multimeter but I can get one and yes, I have no clean signal even if the effect is OFF, so I believe there is no bypass at all.

deadastronaut

are your jacks wired correctly?...  tip/ring/ sleeve=ground
https://www.youtube.com/user/100roberthenry
https://deadastronaut.wixsite.com/effects

chasm reverb/tremshifter/faze filter/abductor II delay/timestream reverb/dreamtime delay/skinwalker hi gain dist/black triangle OD/ nano drums/space patrol fuzz//

mth5044

Perhaps you have the switch oriented the wrong way? Not sure if the LED could still work, but it's hard to tell as they give you no detail about the little board in the build doc.

andresl7

HI. well the switch I believe is oriented the right way because when I press it the led comes on , which i suppouse means that it is properly oriented. I just double checked the build documents  and The jacks seem to be properly connected, I could be wrong though.
However, Here are the pictures up close just in case there may be something wrong with the soldering of the jacks/components/footswitch. let me know if theres anything you can see here.






mth5044

No clean or effected signal usually means something wrong with wiring, switch or jacks. Since the LED is lighting up, the power is likely correct, but it is possible that the LED could still work, depending on how the traces are connected on the board, even with the switch in the wrong orientation. The PDF doesn't show the traces so it's hard to tell. You may have also melted the insides of part of the switch. There are a few burned spots on the PCB you have shown, so it's possible you applied too much heat to the switch and destroyed it. A multimeter would help to eliminate the switch problem.

J0K3RX

Just to rule out the switch and or the little breakout board attached to the switch remove it from the equation... Wire the output from the board directly to the output jack and wire the input on the board directly to the input jack... Wire the ground by the output on the board to the output ground lug, wire the ground by the input on the board to the ground lug on the input jack.

Note (1: Make sure you have "the correct lugs" on the jacks! Easy mistake to make..
Note (2: when soldering stomp switch be quick about it. Some of them are very sensitive to prolonged heat and are easily damaged by the iron tip if dwell time is too long.
Note (3: Sometimes when feeding the solder into the pads on the switch breakout board it can appear that you are adding a ton of solder but it's evaporating or something because the hole is not filling up. Later you discover that all of that solder you were adding is on the other side of the board underneath the switch in the form of a giant ball of solder. This blob of solder can easily cause an undetected short...

test... still no sound? Go to the next thing in line... Start probing the voltages on the board. Also, look for open circuit where there is not supposed to be and look for a short circuit where there is not supposed to be etc...   By going over the board with a meter also gives you time to inspect each and every part and solder joint and possibly find the problem..
Doesn't matter what you did to get it... If it sounds good, then it is good!

duck_arse

+1 wot they said. you needs the meter to make further process. those connections above the Ge diodes, and one o' those diodes, look suss/bad. the wires may be shorting, but you won't know until the meter comes.

and for your next build, just to preserve your sanity, use at least 2 colours of wire. the more colours, the easier-to-spot/harder-to-make wrongs.
don't make me draw another line.

Jef O

Looks like the pcb for your switch is upside down. You should see the numbers 1-9 when looking at the lugs of your switch

andresl7

Hey guys, thanks for all the information. I Apologize so much for taking so long to reply , I just got home from a trip to the countryside. I did manage to fix the pedal, turns out that my solders were very bad so a friend of mine fixed them. The pedal is working now. I just had one final question , I am running it thru a 9v 600ma adapter and I found out that overdrive should be run thru adapters with smaller ma such as 100ma. It does get a little hum ,  But does this decrease in the ma affects the sound of the overdrive effect itself? or are there any other mods that I could do with the overdrive to maybe have a bit more compression? thanks guys for everything  :)

duck_arse

"the ma" is the current drawn. a pedal will only draw the amount of current it needs to get its job done. it doesn't matter what "current rating" your adaptor has, as long as it is more than what the circuit needs. if yr adaptor can't supply enough current, its output voltage will "sag".

some adaptors are better than others, depending on lots of different factors. transformers can have a loose lamination, which will buzz, or low value filter caps. you can head over to amz and look at the "Hum & Noise in Effects" page (all the pages, really, read the whole site). the first circuit shown on that page, built into your pedal, may well make it "crappy adaptor proof". there will be pages on compression at amz, as well.
don't make me draw another line.

jighead81


andresl7

Oh thanks for the explanation about the adaptor. Well, i wouldnt know what this overdrive is based on but i can tell you that I Purchased it from mammoth electronics and they have the build documents right there for download, so maybe you can figure it out friend