Adding a DC input jack to black russian BM - high pitch tone constantly

[Yellow47]

Hi,

I've added a DC power jack to my V8 black russian big muff, it powers on and works but there is a high pitch tone/whistle 'on' all the time.
I have tried it with the enclosure apart, DC jack unmounted, connected wires away from other components and input output jacks but nothing makes an ounce of difference. (My thinking there was some kind of interference between in/out and power)
The pedal works fine with no issues with a battery.
I've tried it with my proper isolated pedalboard power supply but the tone/scream persists.

I've been searching for a while and reading about DC power filter caps but, as probably noticed, I'm a novice when it comes to that.
I can do the handywork but I don't know the theory or how to work out what I might need to add, capacitor wise, to help take the screamer away!

Could anyone give me some pointers on how to fix this?
I would greatly appreciate any help, I couldn't find anything with searching that seemed to fit my issue.
I've (hopefully) added a picture of the wiring of the pedal from 'the' BM site.

[GibsonGM]

What is the DC adapter like?  A regular old non-regulated type, or one made for use on pedals?  If it's the first, it's probably causing the noise all on its own.   You can try adding a 100R resistor in series with the "+" power line, with a BIG cap to ground just after it (like, 470u, or 1000u).  This may help filter off the whine.

With it plugged into the pedal, can you measure the voltage at the DC jack? If it is non-regulated, you may find it's a big....high.....so be sure to try pedal again w/batteries to make sure it is still working.  Did you power it up OK with your pedalboard supply before the other adapter? (thinking whine could be damage from unreg. supply, maybe).    If it's over 10V, 11V 'loaded', I'd find another power brick....

[Yellow47]

Thanks very much for the advice GibsonGM, I really do appreciate it.

It's a funny thing, it's all fine now... I shuffled a few things round again and kinda re-routed my pedalboard power leads and there's zero whine him or anything. So that's awesome.

I'm slightly sad that this is the case because I wanted to learn how to sort this out as a pedal I built a while ago has the same turbo whine. I think I'm just beginning to notice the turbulence of super high gain pedals and how to deal with such issues.

Anyway, all is good and well for now.

Thanks again!

[antonis]

I think I'm just beginning to notice the turbulence of super high gain pedals and how to deal with such issues.

Some guys call it "stray capacitance" but (almost) all try to get rid of it out of the neighborhood.. 

edited

[anotherjim]

Antonis, please repair the above "guys" typo before my non-politically-correct sense of humour gets the better of me!

[GibsonGM]

Glad to hear it is OK now, Yellow!!    Yes, that stray capacitance, hanging around the neighborhood, and up to no good!  I will keep my anti-PC at bay for now.

This demonstrates that parts and wires often radiate energy...they can "COUPLE" with other parts/wires, acting like a little transmitter and receiver.   This can happen inductively, or capacitively - that is above our pay grade right now.    Bottom line is that how you route your wires is important!   

Input wires should be separate from wires coming from stages that amplified signal (just called 'output wires').   If they MUST cross, do so at right angles like a " + ".  If you need to, you can tie them back with cable ties or something, to keep them in position.  I am thinking more about large builds/amplifiers, but you get the point.    You don't want the offending wire to bend back over while you are using your pedal, causing whine again!     

Sounds like self-oscillation was the culprit.   In time, you will learn how to isolate places that will cause this in a way that makes sense, just keep building 

[antonis]

Antonis, please repair the above "guys" typo before my non-politically-correct sense of humour gets the better of me!

(did I catch time limit..??)

[GibsonGM]

Antonis, please repair the above "guys" typo before my non-politically-correct sense of humour gets the better of me!

(did I catch time limit..??)

I think you made it, Antonis...