controlling a linear actuactor

Hi all,

(wasn't sure which section to post this so put it under general)

I got a question for you acuator guys.  I have one powered by a motor with only 2 leads,

Applying power spins the treaded rod in one direction, and reversing voltage polarity spins it an another

What can I use to wire up a simple switch to control the power input?

fyi: I don't need any relay to check/stop the travel at the end or keep power going for x number of seconds or anything fancy like that.

In fact if it behaved like a power window switch and only moved while I press/pulled it, that would be perfect.

OK now don't laugh, it's not for a car project, but my Sears/Weider brand "Crossbow" gym :oops:

the tension is adjusted by a linear acuator and a pulley system, But the control computer died (Weider wants $200 for a replacement computer, not worth it for a fancy switch IMHO)

I am able to splice power to the motor to raise/lower the weight resistence.

Any suggestions on what I should do/use?

Thanks

I'm a bit thrown off by the fact there's no common body ground,

The above was for door locks with multiple switches.  Disregard the parts about connecting to the alarm wires.

Why don't you just use a power window switch?..

Jim

Above is a Double Pole Double Throw On-Off-On momentary switch