Hi Matt
I will try and answer your questions as best I can, I am not a tech by any means, some of my answers could well be better explained by other people. LOL
1. I imported my bits and pieces direct from Shoestring Astronomy, I emailed them first and they replied almost immediately with the cost to send to AU. Time from submitting my order to receiving was just over a week. Shoestring advise you by email when the article is posted.
2. It requires a 6 pin cable with RJ12 connectors. Go to the site here:
http://www.store.shoestringastronomy...roducts_gp.htm
scroll down to the GPINT-PT picture, there is a downloadable manual that has a pinout diagram.
3. ECP (You MAY have to try the others) The free downloadable port checker, I found, used a different port setting, strange.
4. I purchased the following: GPINT-PT, Cable GPFC-14 and a Guide Port Splitter, I still need the use of my hand controller.
5. I can't answer for your mount but my GM-8 without Gemini or DSC's I move by hand and final slew using the hand controller, the autoguider plugs into the splitter and I simply reset my guiding speed to .5x. I had trouble using this system with my G-11 mount with Gemini, I kept getting an autoguider error, so it is not used on the G-11, that is where the ST-4 comes into it's own.
6. As far as I know, it is just a simple 6 pin, RJ12 connector. As far as I am aware, the GPINT-PT is an isolator, you might want to look at the link above and the manual.
Your last remark, I am unable to help you there, I am not electronically savy. I found it was easy to just get the parts as a complete package from Shoestring, everything has worked just fine since I got them.
Hope this helps a little
Cheers
JohnG
