Hi Jon,
I found out how to program receive only channels with CHIRP, but I had to google for it.
Duplex="off" to me says simplex !
Would it not make more sense for the "off" option to read something more meaningful to users "NO_TX" or "RX_ONLY" for example.
Yeah, maybe. A duplex of None means no duplex. The point was to interpret the duplex field as a command, along the lines of "what happens when I transmit". Many radios overload their duplex field/setting/indicator in a similar way.
Changing it now would be a bit of a problem, because people have CSV files out there with "off" and even if we supported that on read, users with new versions of CHIRP would create invalid CSV files for users of older versions. If you want to write a patch to handle it as gracefully as possible, we can certainly discuss it.
Thanks!
--Dan