Re: My new "controller"

[webmaster@ccdemo.org (Leonard G. Barton, Webmaster)]

Black is radio ground, red is radio power (6 volt nominal if used with
alkaline, but useualy 4.8 from 4 nicads), and white is (I beleve) a pulse
width modulated signal from a decoder in the reciever, modulated between
ground an power. You will need to build a modulator, but there are simple
timer ICs that will do this with very little outboard equipment. Sorry, I
don't know the frequency or the modulation range, but you might call a
vendor such as Futaba (714-455-9767 in Irvine CA). I'd suggest using a boat
or car motor for which this was designed and would be concerned about stall
current.

25V at 75A is about 1/4 HP electrical input - this should be plenty for a
scooter.

>Well, I may be going about my next EV project backwards, but I just
>received my first part: an Astro Model 212D Hydro Speed Control. It's meant
>for RC hydro-hull boats, and is maximum rated for 25V and 75amps
>(continuous) -- since I want to use it on a bike or stand-up scooter, a 2hp
>max is plenty (i.e.-probably too much anyway)! It's the size of a cigarette
>lighter, and a little over an ounce in weight, with a red-and-black 13ga
>wire pair on "MOTOR" and "NICAD" ends, and a white-red-and-black trio of
>finer wires...what I need to know is, what does  the control circuit (fine
>3-wires) need for input? The info that came with it mentions "5v at 1amp
>BEC to radio and servos", but that sounds like output to RC stuff...how
>much goes "in", or does it just need a 0-5K pot like a Curtis?
>
>If anyone needs more specs: $50 +s&h (discontinued model), 2800Hz switching
>rate, 4 SMP0N03 MOSFETs (with total resistance <3ohms), 8-bit digital micro
>processor, 2 schotky diodes, and a "voltage doubling mosfet gate drive
>circuit for highest possible efficiency".
>
>I'll be getting a couple dozen used Hawker Genesis batteries in a month or
>two, then will test out different motors...if I can figure out how to
>control the controller!
>
>Russell Levine
>Vacaville, CA