No Flange Signal, Electric Mistress

[dfx_pedalpcbs]

Where in the signal should there be some flanging going on, is it at pin 7 & 8 of the MN3007 because I get nothing there at all

I get a clean signal at the output just no effect, led flashes at the LFO.



All the chips are good and work in other effects so im not sure whats causing this

[iainpunk]

do you have an Audio Probe? that is the best tool for debugging.

the flanging only really happens when you mix the clean and pitch shifted delayed signal together. there should be signal on the output of the chip, but is should sound vibrato-like

cheers, Iain

[danfrank]

You should have flanging where r15, 16 and 17 come together. If you're using the "send & return" jacks, you need to make sure there is a connection to bridge those two jacks when no 1/4" plugs are inserted into those jacks. If you aren't using those jacks, a wire needs to be soldered to the 2 jack's hots so signal goes through.
.
Good luck

[anotherjim]

I'd have thought those send/return jacks should use switched sockets so the signal passes between them when nothing is plugged in.

[StephenGiles]

What are the clock voltages at pins 2 & 6 of the MN3007? They should both be around half +Vc.

[danfrank]

I'd have thought those send/return jacks should use switched sockets so the signal passes between them when nothing is plugged in.

Yes, I was just trying to cover anything that might be overlooked since the provided schematic doesn't show switched jacks.

[dfx_pedalpcbs]

Clean signal at those junctions

MN3007

Pin 2-0V
Pin 6-8.75V

[danfrank]

Pin 2 should be the same voltage as pin 6, the other clock pin.
Probably a solder bridge or cold joint on the PCB or there's something wrong with the clock pulses going to pin 2 of the 3007

[StephenGiles]

Pin 2 should be the same voltage as pin 6, the other clock pin.
Probably a solder bridge or cold joint on the PCB or there's something wrong with the clock pulses going to pin 2 of the 3007

Also remove the 3007 and see if the voltages going to its pins 2 & 6 are the same, if they are remove the 4049 and test voltages at pins 1 & 2 of the 4013. 

[dfx_pedalpcbs]

ok will try those steps and report back

[dfx_pedalpcbs]

MN3007 removed-voltages same

CD4049 removed pin 1 on the CD4013 is 8.75V and pin 2 reads nothing

Tried different LM311 and its now working

Thanks for the help

[StephenGiles]

Good news, I was leaving the 311 until last because I don't know how available they are!

[PRR]

> leaving the 311 until last because I don't know how available they are!

If LM311 goes away, that's the end of the world.

DigiKey shows lots. Limiting to DIP ThruHole, over 9k in stock, under a buck a chip. If you like lead, that's half price.

We OK for today.

[StephenGiles]

> leaving the 311 until last because I don't know how available they are!

If LM311 goes away, that's the end of the world.

DigiKey shows lots. Limiting to DIP ThruHole, over 9k in stock, under a buck a chip. If you like lead, that's half price.

We OK for today.

That's good to know should I run out!

[dfx_pedalpcbs]

This was the batch that gave me head aches!

[danfrank]

Where did you purchase them? It's always good to know where to avoid difficult parts. Thanks

[dfx_pedalpcbs]

ebay but sorry I cant remember the seller