Time to play everyone's favorite game...

[Govmnt_Lacky]

@Mark

I see your point. In my case, it may be a bit different....

As you explained, I definitely get a raised "noise floor" when I crank the Regen on the flanger I definitely get louder Whooshing from it. The thumping however, remains constant throughout the travel of the Regen control.

Remember, I also get the thumping when the pedal is totally BYPASSED as well  I have a gut feeling that some skillfully placed shielded wiring will get rid of the thumping but, I am still stuck on the whoosh AND I am still trying to get a handle on how to wrap and insulate one or both of the PCBs to eliminate the heterodyning.

[GGBB]

Could you point me in the right direction on good ways to "insulate and shield" one of the PCBs? Possibly some pics as an example...

First thing that comes to my head (I've not seen or tried this myself) - put the board in an antistatic parts bag, then wrap that in aluminum foil with a bare grounding wire sandwiched between.  I suppose you could glue the foil to the outside of the bag first with spray glue, but a looser fit might prevent tearing/splitting.

[earthtonesaudio]

I would shield signal wires first, if that didn't fix then I'd add some power supply decoupling/pi-filtering/regulation, if that didn't fix then I'd go for the bag-in-a-bag solution as described by GGBB.

[Govmnt_Lacky]

I would shield signal wires first, if that didn't fix then I'd add some power supply decoupling/pi-filtering/regulation, if that didn't fix then I'd go for the bag-in-a-bag solution as described by GGBB.

Do you think shielding the input and output jacks to the 3PDT will be good enough OR will I need to go to the PCBs as well?

[jimilee]

I had the same issue the other day (or similar) something was grounding out against the pulsing LED in my phaser causing a very percussive sound in bypass and activation too. It probably isn't your issue, but maybe some new ideas.

[earthtonesaudio]

I would shield signal wires first, if that didn't fix then I'd add some power supply decoupling/pi-filtering/regulation, if that didn't fix then I'd go for the bag-in-a-bag solution as described by GGBB.

Do you think shielding the input and output jacks to the 3PDT will be good enough OR will I need to go to the PCBs as well?

If you have the patience do one at a time and check the results after each change.

[Fender3D]

Do you think shielding the input and output jacks to the 3PDT will be good enough OR will I need to go to the PCBs as well?

Try with a RC cell to decouple power supplies first.
You may keep PCBs away from signal wires to check if this is a crosstalking issue...
But I think separate grounds and separate powers will be more effective

[armdnrdy]

Are there a ground planes on the trace sides?

Trace side photos would be helpful.

Heterodyning and crosstalk can occur when the "wrong" traces are too close together.

[Govmnt_Lacky]

Are there a ground planes on the trace sides?

Trace side photos would be helpful.

Heterodyning and crosstalk can occur when the "wrong" traces are too close together.

Larry,

It would be up to Federico to share the layouts as they are his.

I can tell you this.... they do not have ground planes. I am pretty sure the layouts might be part of the problems however, I am trying to work with what I have 

[Fender3D]

www.wizardinside.it/foto/schemi/micro_cR51-sch.pdf
www.wizardinside.it/foto/schemi/micro_cR51-pcb.pdf
www.wizardinside.it/foto/schemi/micro_fR51-sch.pdf
www.wizardinside.it/foto/schemi/micro_fR51-pcb.pdf

Here they are,

Greg, does a single effect (with other without power supply) work ok?
'cause you can get heterodyning only when 2 slightly different clocks interfere each other.

Edit:
corrected link  

[armdnrdy]

Thanks Federico,

The link for the Micro Flanger schematic is here:

http://www.wizardinside.it/foto/schemi/micro_fR51-sch.pdf

[puretube]

I`d just turn both PCBs 180° `round...
(clox AWAY from *hi-Z* input-signals/stompswitches)





[yes, the other sides don`t have cut corners: that`s a different problem...]

[armdnrdy]

Are you using the GGG "two effects in one box" switching that sends the input to ground?

I had issues with that switching.

[Govmnt_Lacky]

@Federico

I was able to get rid of the heterodyning when I pulled the chorus timing caps but, I was still getting the LFO whooshing and the thumping even when the pedal was true bypassed.

@puretube

I suppose I could try turning the boards around but it will not be easy. Wiring may become a problem 

@Larry

I am NOT grounding any of the inputs in bypass.

[puretube]

...
@puretube I suppose I could try turning the boards around but it will not be easy. Wiring may become a problem
...

yet another different problem...


ps: keep LFO signals AWAY from *hi-Z* input-signals/stompswitches...
(eventual LED-wires too...)

[Fender3D]

I was able to get rid of the heterodyning when I pulled the chorus timing caps

Then keep the chorus clock (Q3 and Q4) away from flanger's BBD... (maybe a shield is enough, shield the clock of course)

but, I was still getting the LFO whooshing and the thumping even when the pedal was true bypassed.

You can't have noise when true bypassed...
unless your (ground) wire(s) are not 0 ohms.
Thumping might be a matter of wires crosstalking, though

[earthtonesaudio]

I was able to get rid of the heterodyning when I pulled the chorus timing caps

Then keep the chorus clock (Q3 and Q4) away from flanger's BBD... (maybe a shield is enough, shield the clock of course)

but, I was still getting the LFO whooshing and the thumping even when the pedal was true bypassed.

You can't have noise when true bypassed...
unless your (ground) wire(s) are not 0 ohms.
Thumping might be a matter of wires crosstalking, though

Of course you can.  "True bypass" means a wire, made out of real materials, which means it has capacitance and inductance, and electromagnetic signals in the area can and will couple into it.  True bypass does not mean physics stops.

[Fender3D]

Of course you can. 

whooshing ??

[Govmnt_Lacky]

The LFO "whoosh" is only present when the pedal is engaged.

The thumping is there even when the pedal is bypassed.

[mistahead]

Thumping definately sounds like a RF bleed - its bypassed and still picking up that parasitic THUMP, parallel non-twisted pairs of wires?

The thump is louder than the whoosh when not bypassed would be my guess also, in that its a bigger "BURST!" of EMI than the ever present whooshing.

Maybe just re-describe the application and call the bugs a feature?