So... I want to be able to "turn down" the speed of my electric R/C truck. I know PWM is usually used to do this, But I think I found a circuit that can be retrofitted. I found a variable speed fan in an old PC I was given, and with a 5K pot I can adjust between 0-1K to get the full range of motor speed.

Now here'* what I'm wondering, The circuit uses a LB1861 which seems to be good for 1.5A, I know the motor I want to control has to be over that, Can I use a transistor or MOSFET to 'up' the amperage and make the circuit work?


The datasheet on the LB1861:
http://www.ortodoxism.ro/datasheets/sanyo/ds_pdf

I like sausage.

LOL, I was wondering when this was going to get a reply...

I got ahold of a guy in my SCCA club who came over and showed me how to do it with an NPN a PNP and two MOSFETs. It wastes some of my mAh, but it works.

How did you do this Dame..

Depending the transistors NPN and PNP you would have needed to supply their required voltage/ground to trigger them right?

So, um, why didn't you just get a smaller motor for the truck? or is it one of them cheapies you can't change parts in?

supply voltage powers the MOSFETs and transistors, the LB1861 triggers the transistors, which trigger the MOSFETs.

Like half of this since I only use one direction.
http://www.bobblick.com/techref/proj...e/hbridge.html

It'* a Nikko Silencer. I think is was $20 in 1997. I'm not gonna buy a truck until I can make this work

So, you can't just change out the parts... I had an RC10 way back when, and was an alternate driver for the "Tattooed White Trash" RC Monster Truck racing team here. So when I think RC, I think the "big boys"....

I would be using more VCR parts If I hadn't found this thing in the trash, Makes some of it easier.

I'm into scale rock crawling anyway, so even if I had the cash to have a truck, It wouldn't be useful.