Hi, I seem to recall running my FT 736 with sat32 pc running on a Windows 98 laptop (it has been some time since I have worked any satellites.)
I used a generic USB to RS232 converter unit and a home brew RS232 to yaesu computer control interface that came with my radio. Sorry I don't have a schematic for it.
There are some schematics floating around for the RS 232 to yaesu computer control interface.
This link seems helpful but I can't vouch for it's accuracy as I haven't tried building the circuit.
http://www.mindspring.com/~n2wwd/html/body_doppler_compensation.html
If I was building an interface today I'd probably skip the RS 232 step and try using a USB to 5 volt TTL serial converter (I'd want to double check the voltage levels on the radio interface first but the prior URL implies to me that the voltage levels are 5 volt TTL which seems reasonable to me given the age of the radio.)
Most of the USB to serial interfaces I've seen are 3.3 volt but I seem to recall seeing 5 volt ones advertised.
Hope this helps
Mark S VE7AFZ
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