# Pitch Witch Ticking



## BattleRhythms (Apr 9, 2020)

Pitch Witch is ticking and looking for any solutions.  Ticks in conjunction with speed knob which sets the rate of the LFO LED.

I have verified component values and soldering to be good.  I have tried switching the RC4558 LFO IC with a TL072 and a LM358 as recommended with this issue.

I have also tried series 100 ohm resistor with 10uf capacitor to ground after the power jack and before the board.

Nothing has worked and I am looking for other  thing to try. Thanks in advance!


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## Nostradoomus (Apr 9, 2020)

Using a TL022 cured mine but it wasn’t too bad to start with. 22s are the lowest current draw of the bunch.


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## BattleRhythms (Apr 9, 2020)

Thanks for the reply. Didn’t have TL022s in my stash, but will put in an order for some. Will let you know if that works. I have seen some of your responses on related/other posts. Thanks for your contributions!


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## Chuck D. Bones (Apr 10, 2020)

Another crappy LFO design.  Something like the Sea Horse LFO fix should work.  First order of business is get rid of C15.


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## BattleRhythms (Apr 11, 2020)

Chuck D. Bones said:


> Another crappy LFO design.  Something like the Sea Horse LFO fix should work.  First order of business is get rid of C15.


Got rid of C15 and it seemed to reduce the magnitude of the tick, but it is still there. I am still using a LM358 for the op amps. Will send an update when I replace with a TL022.

Thanks for the advice!


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## Chuck D. Bones (Apr 11, 2020)

That was just step 1.  
Step 2 is to apply the Sea Horse / Dark Rift fix. 
Lift IC4 pin 6 from the pad and install a 100K resistor from the lead to the pad.  Install a 47nF cap from IC4 pin 7 to pin 6.  
It may not look pretty, but it will kill the tick.


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## BattleRhythms (Apr 11, 2020)

Chuck D. Bones said:


> That was just step 1.
> Step 2 is to apply the Sea Horse / Dark Rift fix.
> Lift IC4 pin 6 from the pad and install a 100K resistor from the lead to the pad.  Install a 47nF cap from IC4 pin 7 to pin 6.
> It may not look pretty, but it will kill the tick.



It worked! Thanks again. I used a 10nF. One non-issue is that if I turn the speed knob counter clockwise (faster speed) LED gets stuck to ON until I tweak the both the wave and speed clockwise.


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## Chuck D. Bones (Apr 11, 2020)

10nF is fine.
That LFO stalling is fixable too. 
Remember when I said "crappy LFO design"?  What I meant was _shitty fucked-up LFO design_.


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## thecakeisaspy33 (Oct 19, 2020)

Hello, I have replaced RC4558 with a TL022 cp. 
I have no more ticking problem but I don't have the modulation effect anymore and sometimes the two leds stop working.
Maybe it's another problem ? 
I will try the other fix with the MKT 10nF also.


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