# Madbean Current Lover oscillation



## Chrisq206 (Jan 28, 2022)

I’ve gone over the pedal a bunch and I’m not sure what’s causing the oscillation. To be fair this Pedal is probably a little over my head, but I keep coming back to it to see if I can get it going.

I did do the update with biasing resistor.

A friend of my got it running really quietly, but once it internal trimmer volume gets turned up, off it goes into oscillation.

Any idea where to start on tracking down the problem?

I’m not next to the pedal now, so I’m going on memory as to what I’ve tried so far. Please excuse the lack of detail.

Cheers


----------



## Bio77 (Jan 28, 2022)

As TWS mentioned, sounds like you have the feedback trim set too high.


----------



## Chrisq206 (Jan 28, 2022)

I’ll specifically check into that when I get a chance and get back to you.

Thank you for your help


----------



## Bio77 (Jan 29, 2022)

Here is a thread describing setting up CL with a scope:






						Is Current Lover (2015) Calibration Possible with O-Scope or Frequency Counter?
					

Is Current Lover (2015) Calibration Possible with O-Scope or Frequency Counter?



					www.madbeanpedals.com
				




You can do it by ear with at the same procedure, just listen for distortion, instead of looking for a clean waveform on the scope.


----------



## Chrisq206 (Jan 29, 2022)

I got it working. For some reason the oscillation happens when the input is grounded to the chassis, meaning it stoped oscillating when pulled the jack (Switchcraft) out of the enclosure and disconnecting the ground.

????

Ran out of time to trouble shoot the cause, but pretty happy that it can work at volume without oscillation. Need to figure out the grounding thing and time it better now

Any input?


----------



## Chrisq206 (Jan 29, 2022)

I really need to proof my entries better


----------



## fig (Jan 29, 2022)

Make sure the tip latch on the jack is not grounding to the enclosure (usually on the corner column).


----------



## music6000 (Jan 29, 2022)

Chrisq206 said:


> I got it working. For some reason the oscillation happens when the input is grounded to the chassis, meaning it stoped oscillating when pulled the jack (Switchcraft) out of the enclosure and disconnecting the ground.
> 
> ????
> 
> ...


Are you using the multi choice enclosed jacks below:


----------



## Chrisq206 (Jan 29, 2022)

music6000 said:


> Are you using the multi choice enclosed jacks below:


No, the old school open frame switchcraft style


----------



## Chrisq206 (Jan 31, 2022)

I ended up requiring the in and out as suggested for the effects loop version. Something was was not working with the other way of wiring, but couldn’t figure out what. 

It works now which is a minor miracle. I’ve left this project and come back many time over the last couple of years or so and now it finally works.

There is still one problem though 

When I switch to the matrix setting there is signal, but no effect. 

Any idea why tat might be?

I will probably post another thread on this

Very pleased the flanger side is working and I never use the matrix setting on my EH Mistress, but it bugs me that it doesn’t work


----------



## Betty Wont (Jan 31, 2022)

The "matrix" mode disconnects the lfo so that it stops cycling. If the range and feedback knobs change the sound it is working.


----------



## Bio77 (Feb 1, 2022)

Chrisq206 said:


> I got it working. For some reason the oscillation happens when the input is grounded to the chassis, meaning it stoped oscillating when pulled the jack (Switchcraft) out of the enclosure and disconnecting the ground.
> 
> ????
> 
> ...



Are you saying that with two grounds (one on the input, one on the output) you had oscillations? That might be a ground loop, at least that's what I have read, I've never seen one in the wild   Where is the circuit grounded now?


----------



## Chrisq206 (Feb 1, 2022)

Bio77 said:


> Are you saying that with two grounds (one on the input, one on the output) you had oscillations? That might be a ground loop, at least that's what I have read, I've never seen one in the wild   Where is the circuit grounded now?


This project has two ways to wire the input/output/switch (luckily!). As my other post said, I switched to the other wiring option and the pedal started working. Never did figure out what was wrong with how I did my initial wiring.


----------

