Thank you for your response. I also found out that BINTEL a Australian scope shop sells Shoestring Astro products....
Shoestring Astronomy provides you with two options!
USB port guiding using the GPUSB product
Parallel port guiding using the GPINT-PT product
The
GPUSB guide port interface adapter plugs directly into a USB port on your computer or a USB hub attached to your computer. Using an RJ-12 cable, the adapter connects to the guide port of your telescope mount. This guide port interface uses optocouplers to electrically isolate the computer from the telescope, eliminating a possible source of electrical interference. This interface adapter requires no external power source since it receives its power via the USB cable. More information can be found by
clicking here to view the User Manual. The
GPINT-PT guide port interface adapter plugs directly into the parallel port of your computer. Using an RJ-12 cable, the adapter connects to the guide port of your telescope mount. This guide port interface uses optocouplers to electrically isolate the computer from the telescope, eliminating a possible source of electrical interference. This interface adapter is small and require no external power source. It uses the D4, D5, D6, and D7 lines of the parallel port. Furthermore, all of the parallel port signals are routed through the adapter to another DB-25 female connector so you still have access to all the parallel port signals. If you have a modified webcam or a DSLR shutter control cable that needs to be controlled by some of the parallel port signals (D0, D1, D2, or D3), you still have access to them! More information can be found by
clicking here to view the User Manual.