Cepheid chorus noisy LFO

[Dwubyd]

I finished the pedal but when the pedal is switched to bypass I can hear the LFO if my amp is on crunch.

Is that normal?

Can I use a 4PDT to depower the circuit when it is bypassed?

 

[blackhatboojum]

I finished the pedal but when the pedal is switched to bypass I can hear the LFO if my amp is on crunch.

Is that normal?

Can I use a 4PDT to depower the circuit when it is bypassed?

Are you hearing sweep of the lfo or a tick/thumping sound with the rate of the lfo in bypass?

 

[Dwubyd]

Are you hearing sweep of the lfo or a tick/thumping sound with the rate of the lfo in bypass?

More like a sweep, and only with a lot of gain.

 

[blackhatboojum]

Can you post pictures of both sides of your pcb?

 

[zgrav]

Are you hearing sweep of the lfo or a tick/thumping sound with the rate of the lfo in bypass?

I think powering down the pedal is likely to be asking for a pop in the circuit when it is powered on. also might have some noticeable delay for the LFO to stabilize. but you might be able to use a 4pdt to stop the LFO without powering down the circuit.

have you tried shielding the input and output wires to and from the footswitch?

 

[Robert]

It might be worth moving the Input / Output wires around a bit. If they get too close to the LFO section they could pick up some noise.

 

[Dwubyd]

Thanks guys. I am away for a few days and when I get back I will follow this up.

 

[fig]

I got this! No wait….nope..nevermind.

 

[Dwubyd]

Ok. I'm back.

Photo below.

Ticking happens when I have my amp on high gain (Lead setting on Katana 100). It occurs with the pedal on and off, but it makes a slightly different ticking sound. Power supply is a Fender LVL8.

Thoughts?

Could it be related to the LED connected to the LFO?

 

[blackhatboojum]

Ok. I'm back.

Photo below.

Ticking happens when I have my amp on high gain (Lead setting on Katana 100). It occurs with the pedal on and off, but it makes a slightly different ticking sound. Power supply is a Fender LVL8.

Thoughts?

Could it be related to the LED connected to the LFO?

The LED should have nothing to do with LFO tick. As Mr. Bird suggested, try moving your input and output wires around first and see if the ticking goes away. Maybe run them under pcb and away from the opamps. There's several other things you can do to try and eliminate the noise but, lfo tick can be an extremely annoying with no solution sometimes. Whenever you put an effect in front of a high gain amplifier, any noise that pedal has, is going to be amplified tremendously. Sometimes, things like lfo tick are just the nature of the beast when trying to run effects in front of high gain. That being said though, Try putting a buffered pedal in front of your chorus and see if that helps. You could also try using shielded wire on your input and output. You could also try swapping out your lfo opamp for a different tl022, or maybe a tl062, or a lm358 and see if the tick goes away.

 

[equinox]

Haven't used my pedal since I build it as tied up with other thing, but circled back around and yeah, noticed it "ticks"! I notice it when DISengaged rather than engaged!!

I'll see if moving the wires does anything, but know I my wires are routed to the outside away from the board, so shouldn't be in proximity of anything. I can also try to use shielded cable.

Just bringing it up. Also, I remember some issue or something when released and there needed to be a 68k resistor soldered to the back of the board!! Soo, this was probably an early board and I wonder if any other issues with the early board and newer board and revision needed?!??