To do it that way I think you need USB->USB/Serial converter->Hand controller->mount
Alternately you can go USB->USB/Serial converter->EQdirect->mount
Or USB->USB/Serial TTL cable->mount
heres where you can get the cable if you go for the last option:
http://www.dontronics-shop.com/ftdi-...ter-cable.html
You'll need to change the plug on the end to an RJ45 connector to suit the HEQ5.