Author Topic: Mangler REALLY thin and awful  (Read 5220 times)

Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #15 on: March 23, 2012, 10:52:30 AM »
Ha! feeling super dumb about staring at that for the better portion of the day head scratching. however sounds the same. two sets of ac128s. It's not my first build but I'm stumped.

where next? i'm out of ideas here.

zz

jkokura

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Re: Mangler REALLY thin and awful
« Reply #16 on: March 23, 2012, 11:10:53 AM »
So you have turned the electrolytics around? If you haven't you need to make sure the negative side goes to the round hole, and the positive side to the square hole.

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Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #17 on: March 23, 2012, 11:21:49 AM »
correct. i've flipped them. same sound two sets of ac128s. slightly more response from the pots but no fuzz just icepick thin and volume drop

jkokura

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Re: Mangler REALLY thin and awful
« Reply #18 on: March 23, 2012, 11:28:08 AM »
Your voltages might help at this point.

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bangerang101

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Re: Mangler REALLY thin and awful
« Reply #19 on: March 23, 2012, 11:45:40 AM »
have you re-biased it since you switched the caps around the right way?

Have you tried pnp silicon's (2n3906, 2n2907,) in place of the germaniums? This will help rule out the transistors as your problem. They sell them (2n3906) at radioshack if you don't have any, and you don't feel like waiting to have them shipped to you.

« Last Edit: March 23, 2012, 11:50:08 AM by bangerang101 »
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Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #20 on: March 23, 2012, 11:53:42 AM »
I've rebiased several times also did pop in a pair of 2n3906s same issue.


bangerang101

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Re: Mangler REALLY thin and awful
« Reply #21 on: March 23, 2012, 12:12:19 PM »
If you have a multi-meter you could post some voltages, this would help greatly to see whats going on.

 If your not sure how to test voltages...

Just set your meter to measure voltage (usually indicated by a DC or DCV symbol) and set it to the closest range to 9v (on mine it's 20v). Plug power into the circuit via adapter or battery, and put the red probe onto a leg of a transistor and the black probe to anything connected to ground on the board (or anything grounded offboard for that matter).

Do this for each leg of both transistors and write down the results, and while your at it, check to make sure your getting 9v to the "9v" pad on the board. (BTW, not trying to question your skills/ability, just saying in-case youv'e never been informed on how to test using a meter, because I had this problem for a while when I was starting out, and no one would be specific enough on exactly how to use the meter, but I do apologize if you already knew all of this).

Anyway, try that out and post your results.
Owner of Luck Duck Pedals (LDP)

oldhousescott

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Re: Mangler REALLY thin and awful
« Reply #22 on: March 23, 2012, 01:26:07 PM »
Make sure your Fuzz pot is really a B1K and not a B1M or B100K, etc.

madbean

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Re: Mangler REALLY thin and awful
« Reply #23 on: March 23, 2012, 01:40:44 PM »
Kind of a stumper. Resistor values are correct. Caps have been turned around. Diode looks right. Transistors look to be put in the right way due to the way the leads are spread. Doesn't leave much else other than a proper positive ground supply and fully functioning transistors.  ???
I own madbeanpedals (duh). I am part owner of Function F(X).

mgwhit

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Re: Mangler REALLY thin and awful
« Reply #24 on: March 23, 2012, 03:33:19 PM »
Is it possible that the electrolytics (specifically C2 and C4) could have been damaged before their orientation was corrected?  I imagine with C2 out of the equation you'd probably get a much thinner sound with much less (and less adjustable) fuzz.

Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #25 on: March 24, 2012, 09:33:48 AM »
Hey All,

Really digging the all of the help around here. Hoping the trannies are fine. Out of town now but when I get back in I'll throw the meter on it.

I'm as stumped as you.

ZZ

Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #26 on: March 27, 2012, 03:15:59 PM »
SO...

I probed about with the mangler again today and after changing the electrolytics out for new ones it's alive and kicking. I suppose i fried the old ones good.

That being said I've wired up a 250kA pot in after the switch for an input trimmer and I'm wondering if it isn't the correct value. Would something like 500k be better for this?

The wiring goes... lug one from switch in lug two to pcb in lug 3 to ground.

Almost there with it.

Sweet!

ZZ

pryde

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Re: Mangler REALLY thin and awful
« Reply #27 on: March 27, 2012, 03:24:31 PM »
I used a 100kB pot for pregain in my mangler. Works very well.

sgmezei

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Re: Mangler REALLY thin and awful
« Reply #28 on: March 27, 2012, 03:27:22 PM »
I used a 50kb on mine. I am doing another right now and am going to try a 50kC. You can always experiment and see what works for ya. I have mostly heard of people using 25 to 100k though.

Zerstorte Zelle

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Re: Mangler REALLY thin and awful
« Reply #29 on: March 27, 2012, 07:24:16 PM »
You think the 250k could be preventing the mangler from reaching full gain. i was watching some FF videos on youtube and mine doesn't quit fizz and sustain like the prod. models.

more of a fuzzy overdrive at max. Trannies blown out too?

tomorrow more meter work

zz