Connecting Commander Amplifiers to the FT1000MP Series of Radios

This is the answer I've got from Commander Technologies and is OK with both "D" and "MP" versions. I tried here and is working flawlessly. If I good remember, same connections with Alpha 87A, 86 and 91B. Morel, 4X1AD

The best way to connect to your FT-1000 for QSK, is to use the band data jack on on the rear panel. This Radio has a nice function as when the plug is installed in the jack, the radio will not xmit unless pin 8 is grounded. The last event on the Commander amp. with QSK is that the Key Out line grounds on xmit. You must connect the Key Out line to pin 8 of the band data jack. This will prevent any possible Hot Switching. The Key In line connects to the SS relay driver on this same connector. Leave the relay switch on the FT-1000 off as the Key In line requires only the sinking of +12 vdc @ 55ma. and is well within the the rating for the FT-1000. Only one additional connection remains. For the FT-1000 to xmit when the amp. is in stand-by a jumper must be installed on the Stand-by/Operate switch on the amp.

This is only for Commander owners:

This jumper is a green wire and is stored with a wire tie behind the front panel next to the Stand-by/Operate switch. Cut the wire tie and place this jumper on the unused terminal on the top of the Stand-by/ Operate switch on the side with the purple wires. This jumper is only used for the Yaesu, and we do not install it unless we know that the customer has this radio. To operate the radio "barefoot" with this jumper installed, the Stand-by/Operate switch on the amp. must be in the Stand-by position, even if the amp. is off.