Caesar Chorus Trim Pot

[Sparky_mark]

Hi all,

Im making a Caesar Chorus, nearly finished it but waiting on the right trim pots to turn up as I ordered the wrong kind.
Anyway, what does the trim pot do? I'm assuming its some kind of biasing pot, I've never built anything that needed biasing so any points or info would be great!
Thanks

 

[Kroars]

Hi all,

Im making a Caesar Chorus, nearly finished it but waiting on the right trim pots to turn up as I ordered the wrong kind.
Anyway, what does the trim pot do? I'm assuming its some kind of biasing pot, I've never built anything that needed biasing so any points or info would be great!
Thanks

This should help:

Caesar Chorus

This is a really good build... The speed doesn’t get too fast but it’s an awesome build...

forum.pedalpcb.com

 

[Sparky_mark]

Cool, thanks for that. A lot of good reading and some possible changes I could make also!
Ordered the wrong type of trim pot, of course, so waiting on an order of parts and I'll be able to finish it!

 

[Lewage]

Would it make sense to get no signal if a trim pot is turned too far one way or the other? That’s what was happening with this one.This is my first build with a trim pot. It works great when dialed in, but I wanna make sure I don’t have a bad pot before I box this thing.

 

[Sparky_mark]

From what I remember when I made this that sounds about right but it was a while back. I had a lot of problems when I put it together but that was mainly due to one wrong resistor value and a fake BBD chip, once I figured that out it worked like a charm.
I think that mostly you set the trim pot by ear, I was linked to This build doc from Aion fx that was helpful. Skip to the section about setting the bias by ear.

Hope that’s helpful and good luck!

 

[MichaelW]

Would it make sense to get no signal if a trim pot is turned too far one way or the other? That’s what was happening with this one.This is my first build with a trim pot. It works great when dialed in, but I wanna make sure I don’t have a bad pot before I box this thing.

Yes absolutely, there is a very narrow range on the trim bias where you will get sound at all and an even narrower range where you will get the chorus effect. Do a search on all the Caesar builds and you will see this mentioned. I was prepared for this when I built mine a few days ago, otherwise I would have probably set my hair on fire and screamed for help in the Troubleshooting forum