[TRX] indicates optional arg (RX or TX), RX default
T|F indicates TRUE or FALSE
+If first char of command is '-', eg
+-setNR ON
+command is not echoed to log output.
+
setFilter low-freq high-freq TRX
setMode mode [TRX] // mode = USB, LSB, CWL, CWU, etc.
setOsc freq [TRX] // freq in Hz (float)