Author Topic: Rebote Potentiometer  (Read 1606 times)

billstein

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Rebote Potentiometer
« on: May 18, 2013, 09:34:18 PM »
Just finished the Rebote but didn't have the 25k-B pot for repeats. I subbed in a 50k-B pot. What difference will that make? Could I put a resistor across lugs 1 and 3 to reduce it down to 25k?

Thanks guys

billstein

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Re: Rebote Potentiometer
« Reply #1 on: May 20, 2013, 11:16:05 AM »
I found a parallel resistor calculator, so it looks like putting a 50k resistor on lug 1 and 3 will make it comparable to a 25k pot.

Just for my education, what happens if it calls for a 25k pot but you put a 50k in? Would the first half of the rotation be what the project calls for, going from 0-25K? Then the second half would add something not called for, which could be good or bad I suppose.

DutchMF

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Re: Rebote Potentiometer
« Reply #2 on: May 20, 2013, 11:39:22 AM »
Depends on whether the pot is wired as a voltage divider or as a variable resistor.... could you post the schematic you are working from? I'm probably the only forum member out there that doesn't have the Rebote schematic, but it would really help... In the mean time, read this: http://www.geofex.com/article_folders/potsecrets/potscret.htm
It might just help you along....

Paul
"If you can't stand the heat, stay away from the soldering iron!"

midwayfair

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Re: Rebote Potentiometer
« Reply #3 on: May 20, 2013, 12:20:34 PM »
The repeats will go into oscillation earlier on the pot. Don't strap a resistor across lugs 1 and 3 in an attempt to shrink the pot -- that won't help and might actually make it worse. Put it only across lugs 1 and 2 (12K is a good value for this). You want to make it behave like an audio taper, which I find is in general a better taper for the repeats pot in a 2399 delay, regardless of the value used.