> 2. Some of the newer Com- and LPT-ports are not able to supply enough
> current for a cw-interface with optocoupler or transistor-interfaces
> with only 1 kOhm in the basis-line of the transistor.
I couldn't get any of several different optos to key my FT-1000MP, but a
simple transistor interface works fine. 1K resistor in line with RTS to
base of 2N2222 or 2N3904 with DB9 ground to emitter. Then cable from
transistor collector to PTT pin and emitter to rig ground. Works fine with
1000MP line, Icom 706MKIIG, and Icom 756PROII for sure.
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