Icom 718 Rigs do not have a serial port command for the Transmit Function. The RTS or DTR can be used to impliment a circuit that can pull the PTT to a ground state that causes the rig to go into transmit mode. However - requires two serial ports to impliment the functions of rig control and another one to actually pull the PTT low.
Icom 7000's however do have a Transmit function that can be sent as a serial port command as a CAT interface which does not use the RTS or DTR lines.
I enjoy the IC-718 rigs and they are great for their simplicity - however parts have to be done as hardware control to effect the transmit function - I usually set the VOX control for the transmit function - and that works without the hard interface to the PTT. Been using that for 3 years. I just use the direct patch cables for transmit audio - with a remote monitor to prevent overdrive - and another patch cable for the recieve audio from either the speaker or the headphone port to the line-in.
Hope this helps.
Guy - KI4TLY
Kiss principle. The more complex a solution is - the more likely something is really going to go wrong.
On Monday, September 29, 2014 9:10 AM, "'Frank Dinger ,GM0CSZ' ***@gmail.com [linuxham]" <email@example.com> wrote:
In a terminal do the following ;
sudo adduser < yourusername> dialout
When entering your user name do not include < >
Frank GM0CSZ / KN6WH in IO87at