Adding a warp pot to Rebote 2.5

[muehring]

Hi, I'd like to add a warp pot, similar to the one on the d'lay to a rebote 2.5.  I tried replacing the 15k resistor with a 10k resistor and a 5kb pot, but I'm not getting it to oscillate with that combo.  I'll try a 4.7k resistor and 10kb pot next.  Anyone know what would work for the warp pot?
Thanks!

[midwayfair]

Hi, I'd like to add a warp pot, similar to the one on the d'lay to a rebote 2.5.  I tried replacing the 15k resistor with a 10k resistor and a 5kb pot, but I'm not getting it to oscillate with that combo.  I'll try a 4.7k resistor and 10kb pot next.  Anyone know what would work for the warp pot?
Thanks!

The 5K pot in the D'Lay is a trimmer to set the "minimum" oscillation, basically just to make the switch still work when the repeats pot is at 0. Simply connecting lugs 2 and 3 of the repeats pot should create oscillation as long as you aren't at minimum repeats. You need some resistance to ground.

Post a link to the schematic and layout you're using for the Repote and then describe what you've done and I can probably give more specific advice.

[muehring]

Thanks for replying Jon!
Here is the schematic. 

From lug 2 of the repeats pot I ran a 10k resistor connecting to lugs 1 & 2 of the 5kb warp pot.  Lug 1 of the warp pot connects to the .1uf cap.
Basically trying to do the same as this d'lay with warp pot.  I built a d'lay this way, but the warp on the rebote isn't working the same.

[midwayfair]

What's your momentary switch connected to?

[TNblueshawk]

For what it's worth I've used a 10k pot and 4.7k res for the warp pot on Barry's D'lay which works better, IMO, than what the BOM calls for over there.

[muehring]

I'm not using a momentary switch.  I'm just replacing the highlighted 15k resistor with a pot and resistor.

[midwayfair]

I'm not using a momentary switch.  I'm just replacing the highlighted 15k resistor with a pot and resistor.

Well, there's your problem. I thought it was something like this but I didn't want to assume.

The warp pot is supposed the minimum resistance applied between ground (via lug 2 of the repeats pot) and lug three of the repeats pot when they are connected via a momentary oscillation switch (which is a connection that's only made when the switch is pressed). The less resistance you have between lugs 2 and 3, and the more resistance you have between lug 2 and lug 1 (ground), the more repeats you get (it's a voltage divider -- that's what happens when you turn the Repeats pot up). Get the repeats high enough and you get oscillation. The warp pot basically sets how quickly the repeats get out of control when you hit a momentary switch to create auto-isolation.

In your case, you've simply put a resistor and pot in series with the resistance from lug 2 of the repeats. All you're doing with the warp pot right now is increasing/shrinking the size of the 15K, which is really just kind of like making a really, really small adjustment to the repeats pot (like 10% of the rotation).

If you look on the layout you posted, there's a little blue pad just south of where the warp pot is hooked up. That's one side of your momentary. The other side of your momentary is connected to lug 1 of the warp pot -- also colored blue.

[muehring]

Thanks guys!  A 10k pot with a 4.7k resistor seems to do the trick I'm looking for without using the momentary switch.  I do want to add a momentary switch to a different delay to get the instant oscillation to come in.  I have to finish my hamlet first and two abdx boards came in the mail today