My univox super fuzz pedal kit won't work

Started by snow123, March 09, 2021, 04:57:33 PM

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antonis

#120
Quote from: snow123 on April 28, 2021, 06:50:24 PM
i had the DMM on 200 DCV btw

ΒΤW, you DON'T follow what you're told to do..

Quote from: antonis on April 28, 2021, 03:55:26 PM
Black probe in COM (GND) and Red probe in place of Black one (VΩmA)..
(and voltage range selector on 20VDC)

P.S.
Except Q4 & Q5 "over-saturated" indication, Q3 (phase splitter) isn't very happy with only 300mV B-E drop..
You might get yourself a better DMM.. :icon_wink:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

tl-ww-ext


I think your transistors are the wrong  way around...
[/quote]

the kit came with p2n2222a's but im using regular 2n2222a's.
[/quote]

Sorry for beating the dead horse on this, but...  My GGG kit came with PN2222a's NOT P2N2222a's.  PN2222a's and 2N2222a's (that you're using) appear to have the same pinout and it should be oriented opposite what's drawn on the pcb.  I could be wrong, but I still think this is an issue.

T

duck_arse

in the build doc quoted in the first post, the transistor outline printed on the board shows correct for BC series transistor, or for the P2N2222's which we know pin the other way to PN2222. [2N2222 should be metal can, PN should be plastic.]
http://generalguitargadgets.com/pdf/ggg_superfuzz_lo_mods.pdf

we know this because the board also shows e b c markings. however, in the last show photo of the offending build, we see the silkscreen is reversed, and is now correct for PN2222's.



so to my eye, IF snow123 has fitted PN2222's, they are correctly oriented. a photo of the transistors showing the part number would be ..... illustrative.
the circuit output is not the input. the reverse holds true for the circuit input.

tl-ww-ext

OK, I missed that - sounds like they're good then on the orientation.  Thanks,

T

duck_arse

I say flog the dead horse until you see a photo of it. and voltage measures, obviously.
the circuit output is not the input. the reverse holds true for the circuit input.

antonis

Quote from: duck_arse on April 30, 2021, 11:34:14 AM
and voltage measures, obviously.

7 pages and not properly taken voltage readings yet.. 8)

Quo usque tandem abutere, snow123, patientia nostra?  :icon_mrgreen:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

snow123

Quote from: antonis on April 30, 2021, 03:56:07 PM
Quote from: duck_arse on April 30, 2021, 11:34:14 AM
and voltage measures, obviously.

7 pages and not properly taken voltage readings yet.. 8)

Quo usque tandem abutere, snow123, patientia nostra?  :icon_mrgreen:

i did the transistor voltages, do i have to do voltage measures on everything else?

antonis

Quote from: snow123 on April 30, 2021, 04:38:24 PM
i did the transistor voltages, do i have to do voltage measures on everything else?

Of course you did but those voltage readings are inaccurate..
(mostly due to your particular DMM's inaccuracy..)
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

snow123

#128
ok, all of the resistors and diodes are grounded

snow123

and all the offboard wiring is grounded

snow123


snow123


antonis

Quote from: snow123 on April 30, 2021, 05:02:12 PM
ok, all of the resistors and diodes are grounded

OK but I measure 18 (or 19, depending on R22 setting) not grounded resistors..

"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

antonis

"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

snow123

Ok, how much should the transistor voltage readings vary from GGG's chart of voltages?

andy-h-h

Any consideration for starting with a smaller build and getting a few of those to work, then come back to this later?    ::)

snow123

welp i just plugged it in and when i turn it on it just creates static without letting my dry signal through, and expand knob controls the level of the static and depending on what components i touch in the pcb it stops the static. so im thinking some of the caps might be an issue 'cause i couldnt really check the continuity of the caps and im using a mylar and a ceramic cap instead of polyester film caps. and there could be a couple of shorts is certain places.

snow123

i also changed out q1 since it was pretty suspicious with the voltage readings.

snow123

Quote from: antonis on April 30, 2021, 05:47:24 PM
Quote from: snow123 on April 30, 2021, 05:02:12 PM
ok, all of the resistors and diodes are grounded

OK but I measure 18 (or 19, depending on R22 setting) not grounded resistors..



i meant my DMM beeps when i put one lead on the leg and the other lead on the joint

aelling

One of the legs of R1 is in the wrong solder pad, I've marked in purple which leg it is and which hole it needs to go in ( :icon_mrgreen:).

Fix this and report back.