does anyone have the correct blue box voltages?

Started by roofer1, April 17, 2007, 04:54:25 PM

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roofer1

i have built this box from tonepad, all original parts etc.
http://tonepad.com/getFileInfo.asp?id=73
it was working, i gave it to a friend of mine who put it in a box, then it stopped working.  when bypassed fine, when on nothing...  i audio probed around the flipflop and there was no guitar signal there, there is a really loud fuzz/feedback on d2 and c7 (possibly elsewhere but that is what i've found so far).  the guitar is getting into the board as i had clean signal at r23 and c1.
ic1 (cd4013) is showing battery voltage at pin8 (which according to the schem is right), there is battery voltage at pins 1, 3, 12, 14 and at pin 11 its about .5 volt less than battery.
does anyone have the voltages that it should be?  i dont understand how it could work but in the box it stopped working and now is not doing much at all (out of the box).  somthing probably grounded out but now i cant figure out what the deal is...
i searched through the archives and found people with numerous blue box problems, but there were no correct voltage posting (that i could find) and nothing quite like this...

thanks a ton!

roofer1

does it get more bizarre than this???  now with the battery measuring about 8.5v when its plugged in there isnt even that going into the board, i mean there is not battery voltage at the dc jack (which the battery is going through).  anyone ever heard of a dc jack going bad?

Barcode80

check to make sure when it was boxed that you don't have something grounding the circuit to the enclosure. this would cause you to get no sound when the effect is there, but sound when bypassed. are you using plastic dc jack or metal? if it is metal and you are using a metal box, you will create a direct connection between hot and ground, in which case your voltage (which is actually the potential current travel from hot to ground as i understand it, someone please pipe up if i'm wrong) would read zero. it also means you can fry that battery if you aren't careful.

roofer1

yeah, the battery just got really hot (its not in the box) which tells me that when my friend put it in his box, something changed.  the dc jack is a standard metal one and he said he thought one of the pots lugs might be grounding against the box or somthing.  now the pedal is reading some crazy really high voltages (much higher than a normal 9v could supply) and it isnt doing anything when on.

jlullo

roofer, do you have your switch oriented correctly?

on my first pedal, i had mine rotated 90 degrees so that the holes in the switch lugs went left to right... they are supposed to go up and down.  are yours like that?


Barcode80

that's not a joke, that's a valid question. please be respectful when people try to help.

roofer1

right, i get it.  yes, the switch is oriented properly.  see the thing is, this pedal used to work, was then put in a box (stopped working then) and now will do nothing except bypass.
would voltage measurements help anyone here?