Al,
There's a better alternative to EQDIR that replaces it, the usb-serial adapter and associated usb and serial cables with a single cable that plugs into the usb port at one end and the mount at the other. All the circuitry is contained within the USB plug.
http://www.dontronics-shop.com/ftdi-...ter-cable.html
This approach is simple, reliable, less cumbersome and lower cost.
Peter.