View Single Post
Old 01-01-2009, 05:24 PM   #80 (permalink)
MPaulHolmes's Avatar
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,202 Times in 765 Posts
3 wire vs 2 wire Throttle

Well, it's easier (for me) to use a 3 wire throttle, but since the PB-6 throttle is standard (and is 2 wires), the controller will use a 2 wire throttle. That's sort of annoying, because I have to add 2 more electronic components, a resistor and an LM317 voltage regulator (which costs a whole 35 cents!) that will be used to make a constant current source, so that when the throttle's resistance varies, you get a voltage that ranges from 0 to 5 volts. The down side is, now it would have to be a 5k pot that's used, and with a 3 wire pot, you could use just about any range you want, 10k, 5k, 1k, etc... Oh well. I ordered 4 LM317's on ebay for $1.99 (with free shipping!) from Thailand I think, so it should be here just in time for next christmas.

I also added high pedal disable. I programmed it "In System"! I didn't unplug the chip from the circuit! Hurray! I'm not sure how the high pedal disable usually works, but in my case, let's say the pedal is pushed down when you turn the key on. The controller still turns on, but it just waits for the pedal to be all the way released before allowing the throttle to be used, so it doesn't hang and make you turn the car off again.
kits and boards
  Reply With Quote