[Elecraft] [K3] splitting RS232 output for 2 serial ports

[Richard Ferch]

You're talking about connecting one RS-232 connector on the radio to two 
COM ports on the computer, right? You need to think about which lines 
are driven at which end. TxD, RTS and DTR signals are all created at the 
computer to be read at the other end; connecting line drivers from two 
different COM ports to the same receiver on these lines might not work. 
RxD comes from the radio to the computer; splitting it out to two COM 
ports might be OK, but wouldn't serve any purpose.

I think it'd be safer just to route DTR and RTS to one COM port and 
leave its RxD and TxD unconnected, and route TxD and RxD to the other 
COM port and leave its DTR and RTS unconnected.

73,
Rich VE3KI


W4AFP wrote:

> Do you think there would be a problem in letting both signals pass
> through to both COM ports? Wouldn't COM 1 only "look" for the
> appropriate rig control signals and COM 2 only "look" for the
> appropriate CW keying signals? Or not...?