ADA Flanger isn't passing signal

[oldschoolanalog]

If those numbers are V's they are WAY high. You should have no more than ~15V at any pin of the IC's. Check the V regulator (in & out)  then see if anything was damaged by those high V's; especially the MN3010.
Dude!

[Paul Marossy]

If those numbers are V's they are WAY high. You should have no more than ~15V at any pin of the IC's.

+1

[Lurco]

you sure have your meter set to voltage DC? and measure versus ground?

[nbabmf]

I think it may have been on VAC last night.  I made sure the meter was set to VDC, and here are the correct values:

728 612163-1
P1 - 13
P2 - 5.6
P3 - 12.5
P4 - 14.2
P5 - 13.4
P6 - 12.3
P7 - 12.8
P8 - 7.6
P9 - 7
P10 - 6.9
P11 - 0
P12 - 3.8
P13 - 3.9
P14 - 2.2

MC1458P
P1 - fluctuated ~2-12
P2 - 6.9
P3 - fluctuated ~5-9
P4 - 0
P5 - 6.9
P6 - 6.9
P7 - fluctuated ~5-8
P8 - 13.9

RC3403A
P1 - 13.1
P2 - 12.7
P3 - 6.5
P4 - 13.8
P5 - 7.1
P6 - 7.6
P7 - 7.6
P8 - 13
P9 - 12.9
P10 - 12.8
P11 - 0
P12 - 12.1
P13 - 13
P14 - 13

LM343N
P1 - 4.6
P2 - 4.6
P3 - 4.5
P4 - 13.7
P5 - 13
P6 - 11.6
P7 - 12.9
P8 - 12.8
P9 - 12.2
P10 - 12.9
P11 - 0
P12 - 6.5
P13 - 12.9
P14 - 12.9

CD4007UBE
P1 - 0
P2 - 0
P3 - 0
P4 - 0
P5 - 0
P6 - 0
P7 - 0
P8 - 0
P9 - 0
P10 - fluctuated ~6-9
P11 - fluctuated ~8-9
P12 - 0
P13 - 13.8
P14 - 13.8

CD4047BE
P1 - 13.8
P2 - 0
P3 - 8.2
P4 - 13.8
P5 - 13.8
P6 - 13.8
P7 - 0
P8 - 0
P9 - 0
P10 - 7
P11 - 6.9
P12 - 0
P13 - 13.9
P14 - 13.7

MN3010
P1 - 15
P2 - 7.8
P3 - 8.4
P4 - 1
P5 - 8.4
P6 - 7.8
P7 - 0
P8 - 9.3
P9 - 8.6
P10 - 7.1
P11 - 0
P12 - 7.8
P13 - 9.2
P14 - 9.3

I also probed the voltage regulator...

MC78M15CT
Input - 21.8
Output - 15.4

And the little JFET...

LS4393
Gate - 12.1
Source - 14.5
Drain - 14.5

[nbabmf]

Nobody has any input?

[fpaul]

Have you tried an audio probe to find out where you are losing the signal? Find a schematic and trace the signal path starting at the input jack.  The chip datasheets will give you an idea for where you should hear audio.  Also look for anything obvious like broken wires.  If you do a search, Paul has a debugging thread which should give you some leads, also has voltages for the 3010 chip.  Your voltages for that one look in the ballpark.  Hope that helps.

[Paul Marossy]

Have you tried an audio probe to find out where you are losing the signal? Find a schematic and trace the signal path starting at the input jack.  The chip datasheets will give you an idea for where you should hear audio.  Also look for anything obvious like broken wires.  If you do a search, Paul has a debugging thread which should give you some leads, also has voltages for the 3010 chip.  Your voltages for that one look in the ballpark.  Hope that helps.

I agree on the audio probe suggestion. I would have never figured out how to repair any of the real ones sent to me without using an audio probe.

[nbabmf]

I found Paul's debugging thread.  I did a search before I made this thread, and I must have missed it...
http://www.diystompboxes.com/smfforum/index.php?topic=73101.0

[nbabmf]

I can't read the schematic well enough to see where everything is going. I've been flipping the board over while it's plugged in trying to trace the signal path... probably testing my luck with that live AC in the corner.

I'm about ready to send this thing to someone.

[Paul Marossy]

I can't read the schematic well enough to see where everything is going. I've been flipping the board over while it's plugged in trying to trace the signal path... probably testing my luck with that live AC in the corner.

I'm about ready to send this thing to someone.

I've fixed a few of them for people. They are not real easy to troubleshoot due to their complexity, but there's only so many active components to go through. As long as it's not your MN3010 chip, all the rest of the active components are readily available. That LS4393 is also impossible to find, but there are some substitutes that will work.

[nbabmf]

This morning, I managed to find the legible schematic I was using before, and started probing.  I didn't get very far before I knew something was wrong.  Signal gets a LOT quieter after IC1a, which is the quad op amp RC3403ADB.  The next step now is to make sure it's getting the right voltage - if yes, then I'll replace it, and if not, I need to see if there's anything failing prior to that IC's voltage in.  I get the impression that I can substitute something more readily available if I can't find a 3403... maybe an LM324.

I'm tempted to just pick up a couple of every IC in this pedal, except for the MN3010 of course.  It's unlikely I'll find much at Radio Shack.  Does anyone have any input on the NTE stuff that Fry's carries?

[oldschoolanalog]

That LS4393 is also impossible to find...

This any help?
http://www.mouser.com/Search/ProductDetail.aspx?R=PN4393virtualkey51210000virtualkey512-PN4393

[StephenGiles]

You would do better to simply remove that transistor and forget about the noise gate, which is not really needed.

[Paul Marossy]

That LS4393 is also impossible to find...

This any help?
http://www.mouser.com/Search/ProductDetail.aspx?R=PN4393virtualkey51210000virtualkey512-PN4393

I tried one of those in a broken one once, and it didn't work. It did work in my MN3007 clone, however. 

You would do better to simply remove that transistor and forget about the noise gate, which is not really needed.

That's not necessarily going to help. In the few that I have fixed, it ranged from the JFET being bad to any of the various opamps being bad.

[nbabmf]

I took the JFET out and tried a couple others I had lying around.  Nothing helped, so I just put it back in.

[nbabmf]

It ended up being IC2.  I purchased replacements for all the socketed IC's except for the MN3010, and replaced them one by one.  I should have done that in the beginning.

This pedal sounds ridiculous.

[Paul Marossy]

It ended up being IC2.  I purchased replacements for all the socketed IC's except for the MN3010, and replaced them one by one.  I should have done that in the beginning.

This pedal sounds ridiculous.

Yeah, so far in all of the ones I have fixed, it's been either that FET or one of the quad opamps that have went bad somehow. Glad you got it fixed.