Of course I want to connect my transceiver to the computer. It's easy for logging and by turning around the bands looking for strange foreign signals. It's even possible to put the set on an other place than where the computer is. (Using FTP). At the website from the FRAG I found a schema of a CAT-interface using the MAX232. The MAX232 converts the RS-232 signals to TTL level what the transceiver wants to see. I made the interface on a piece of strip line PCB. This design works fine for me on the FT857 and 897. Because I always use the CAT-interface I did not wire out a hardware PTT contact, but use a CAT signal to switch from RX to TX. Almost every software package has the possibility to use this option that's why I did not wire a hardware PTT contact
Drawing as PDF : Sound_Cat.pdf