I had a coiled Shoestring Astronomy cable which worked fine with a PHD, G8 and GPUSB. Wheb I tried to use a flat RJ12 cable from Jaycar (or maybe Dick Smith I forget who) it didn't work. On looking carefully at the cable, I noticed that the pin-to-pin setup wasn't what it should be according to the
Shoestring Astronomy site . I have ordered a flat cable from SA--$US11 inc P and P--saves stuffing around and won't break the bank.