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Old 07-31-2016, 11:34 PM
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Rvjimd Rvjimd is offline
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Default Re: 1/16 Oliver Dozer Conversion

I hope I don't jinx myself but I think I figured out the problem I was having with the sabertooth!

First I have to say, I can't believe the dimension engineering help desk never asked or suggested this... All I got from them was some nonsense about regen and battery capacity, they even suggested that I try a 2000mah battery Ya, where am I gonna put that sucker in is tiny dozer?

Anyway, maybe this will help folks with similar trouble.

I was about to see if a slot car motor would replace the motor on the back end of my gear drive units when I realized the carrera digital motors always use capacitors across the motor leads to suppress noise. So I shortened the motor leads as much as I could, added a cap to the pos and neg poles and grounded them to the can. I also wrapped the signal wires from the blabber tooth to the RX with foil.

Here is a link to one site that I referenced to help with the solution.

https://www.pololu.com/docs/0J15/9

If you guys are thinking, "I always add capacitors to my brushed motors" you won't hurt my feelings if you say so. I just never even thought about it, but it makes sense now! I used to race associated 1/10 scale pan cars on a paved oval and we NEVER installed the caps on the motors back then and that was with old Futaba fm radios and old novak speed controllers.

I have run two battery packs with not a hint of trouble.

I bet on a bigger conversion where stuff is not literally right on top of each other, the problem might not happen.

When the blade servo had the jitters before, I always thought, that seems like radio interference?

Thanks for putting up with my rant...

Jim

Last edited by Rvjimd; 07-31-2016 at 11:37 PM.
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