Well, it's academic, then.  I've used a Airtronics 8ch helicopter
transmitter with a car-freq crystal in it for many years to control things
from sailboats to model tanks :)

Ken

-----Original Message-----
From: Sean Breheny <shb7@CORNELL.EDU>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Thursday, September 03, 1998 1:31 AM
Subject: Re: How to control an RC car


>At 12:57 AM 9/3/98 -0500, you wrote:
>>
>>They may have a different system on each radio :) how else to get us to
buy
>>more accessories?
>>Well, I'd say it's meter time.  With the more complicated radios, it's
hard
>>to imagine that they could do servo mixing and reversing with only analog
>>components, I know it's possible, but YECCCHH.
>>
>>You could always use a xicor EEPOT, they make them up to 6 in a package,
>>pure resistance output on two pins.
>>
>
>I wouldn't doubt it if they have changed their system several times. You
>are right about it being "meter time", but unfortunately my transmitter is
>back home and my meter and I am here :) I'll check when I get a chance.
>
>I agree that it would be a MAJOR kludge to accomplish servo mixing,
>nonlinear rates, etc. with all analog components, but remember, AFAIK, all
>that is done in the _active_ transmitter.
>
>Now that I think about it, one does have to check to see if the servo
>reverse switches are the same on the main transmitter and on the buddy box,
>so I am not sure if that indicates that it is more complex than just pots
>connected to wires. Also, the dual rate switch on the the buddy box works
>independently of the controls on the main box. However, reverse and dual
>rate would be fairly easy to accomplish in just passive components. I
>DUNNO. As you suggest, I'll check with my ohmmeter.
>
>OTOH, isn't all this irrelevent to the original question? AFAIK, the RC car
>equipment works significantly differently from the RC plane equip
>(different freq., different controls, fewer channels, different box style).
>Also, there are no buddy boxes for cars, are there? (what's the worst thing
>that you are going to do with an RC car :), as opposed to killing
>someone(possibly) with an RC plane in an 100 MPH+ dive). So, my main
>original point is that it would seem to me that since there are no buddy
>box capable RC car transmitters (that I know of), one would need to adapt
>an RC plane box to work with the car's receiver. If you can't get an RF
>module for the plane box that is the same freq. as the car's receiver, the
>whole point is suddenly very academic :)
>
>Sean
>
>+--------------------------------+
>| Sean Breheny                   |
>| Amateur Radio Callsign: KA3YXM |
>| Electrical Engineering Student |
>+--------------------------------+
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>