[amsat-bb] AO-40 question(s)

[Ron Overdrive]

So I'm considering putting together something that can work AO-40 and
similar satellites, but everywhere I look says you need 2 radios or full
duplex. Never really said why so I'm curious why its required to have 2
radios (which just seems more complex & expensive) or full duplex
to operate on this HEO. Couldn't I use a laptop and a data cable to control
a rig like a Yaesu FT-817 to line up the Rx and Tx?