I also use a Gearmo 4-port USB/serial converter. Got mine from Amazon: http://www.amazon.com/FT4232HL-Professional-Retention-Certified-Microsoft/dp/B004ETDC8K/ref=sr_1_2?ie=UTF8&qid=1355712034&sr=8-2&keywords=gearmo+usb+to+rs-232 Phil – AD5X