I'm going to be doing all future remotes for direct TV systems using RS-232. I went through the threads which helped, but I was still having a problem. I finally solved the problem which was the use of a null modem 232 cable. I didn't see any threads mentioning the use of a null modem cable.

I'm using the Iogear GUC232A USB to serial adapter and both the H & HR-20 are working at 9600. I haven't had any doubling on any of the keys. Hope this helps!

[Link: remotecentral.com]

"Second, make sure you are using a null modem adapter between the CM232 and the USB to Serial adapter - also make sure the CM232 is firmly plugged in to the RP6...stranger things have happened."

Possibly this has been answered, but does the HR20 support 2 way?

Sweet! I contributed something usefull! :)