Relay

Is there a way of using a servo to control a car relay to turn on an eBay speed 900 like motor? (other than have a servo hit a microswitch which turns on the relay)

The microswitch way you described is the best way I can think of, either that or a battleswitch I suppose.

Any means to do what you have in mind will bring more points of failure, add size and weight, and very possible, a higher cost than a battleswitch.

I'll ask around if one of the Dutch still has one of the several full integrated setups.

Also, if it is to control a Speed 900 that can be stalled... A 30A car-relais is a tad light for that job.

I've found that a simple servo and microswitch works well enough for controlling a relay. In Inertia XL I use 2, 70A automotive relays (one for each speed 900) and haven't had any issues as of yet.

I got pointed towards these for hacking a servo into a Battle Switch:

http://trebor69.tripod.com/speedcnt.html

http://www.rc-airplane-advisor.com/elec ... oller.html

But both use MOSFETs and have a complete circuit. I'm unsure of what you need to do to to just make a servo turn a Relay on and off.

Can someone post a link for a battleswitch,

http://www.technobotsonline.com/?subcat ... ch&x=0&y=0

Never noticed the double battleswitch before

the double ones isn't duel ended like an electronize/team delta switch, both relays fire at the same time. Useful if you want to switch to different voltages/circuits at the same time.