I purchased this about a year ago to try out AstroArt's autoguiding with a video/web cam. I soon found out that I needed to add a second relay (The OptoCoupler) and then found I needed to add battery power to the OptoCoupler's cable and finaly got the whole thing to be able to move my mount through the computer only to find out that AstroArt's autoguiding wouldn't work.
So I gave up on it.
The StarlightXpress Autoguider Interface is barely used and also hard to find.
I'm putting this one up for sale for $100.00 and I'll also include the OptoCoupler and the powered cable I made. and I'll ship it insured in the lower 48 states.
I can accept Credit Cards thru PayPal and I'll accept Money Orders or a Certified Check.