PC power supply and GEM mount

I have a Synta HEQ-5 GEM mount. It takes 8 D-cell batteries to power the motors. I have a PC near the scope, and I'm thinking of using one of the 12v outputs from the power supply in lieu of the batteries.

Is this a bad idea? I want to save money on batteries, but I don't want to risk damaging anything. FWIW, I have everything behind a UPS, so I think I'm ok in terms of power spikes and sags.

Garry Buck

PC power supplies tend to be better regulated than the cheapo power "bricks" commonly available. Not just that, but even a cheap PC power supply can easily give you 10 amps at 12V DC...more than enough juice to power even the hungriest scope setup. And finally, if you're concerned about interference, don't be...if it doesn't interfere with the sensitive high-speed electronics inside a typical computer (where the power supply sits mere inches from the CPU), it won't interfere with anything you might use at your scope.

With rechargeable Gel-Cell systems such as "Jumpstart" available for as little as $23 from on-line auction sources, why risk crashing (or worse yet) damaging your PC as a result of feedback pulses from the steppers or rapidly changing current levels should an uh-oh happen with the external load (yeah, but that stuff never happens, especially in a wet, dew-prone, outdoors environment... right Murphy? )

You could also fabricate a system yourself, though the ready-made commercial units are less expensive than buying the parts and doing it yourself! I prefer Gel-Cells batteries, as they hold their charge for an extreme length of time (we're talking months, not days!), can be readily recharged numerous times from any level, and do not tend to dip dramtically as they are discharged.

http://www.astro-nut.com/gel-cell.html

This allows you to have complete portability as well, be it to go to a further corner of your yard or to a remote site where an AC source is just not available.


Cheers,

Paul

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