PC Interface
I use this simple interface for parameter changes in both the FT-7800 and the FT-60 radios with a homebrew adaptor cable because the FT-7800 uses a mini din and the FT-60 uses a 3.5mm connector. IC1 is of course a MAX232 (RS232-TTL Convertor). All capacitors are 1uF electrolytics and the diode D was a 1N4148. As this circuit needs fed with a +5volt regulated supply ( a few milliamps of current ) it is good practise to make the capacitor nearest to the +5v supply (marked CT ) a tantulum type with a working voltage of 6.3v to give protection against supply reversal or overvoltage.
AK
Interface connectors
The FT-7800 uses a similar connector to a mouse or keyboard and ground (ov) is on pin 2 and the clone data connection ( note this is output as well as input ) on pin 3. IMPORTANT: ensure you NEVER connect the pc DIRECT to these radios as the RS232 levels (plus & minus 12v) will damage the radios. The level convertion is done by IC1. The FT-60 uses a 4 pole 3.5mm jackplug. A= ground (ov) and C= clone data. I could not source a 4 pole at first and temporarily used a standard 3 pole jack which has A and B joined, however B is the external mic input so this was no problem for the small duration this connection was used.
AK