[Yaesu] Yaesu FT-897 - Linear Amplifier Control

[Joe]

My Yaesu rig is the FT-897 and I want to drive the Heath SB-200 amplifier. The instructions in the FT-897 manual for keying a linear, (other than Yaesu's own linear), do not seem to work. There must be some internal changes that have to be made in the rig,  but I do not have any information on them. 

I would appreciate any help in resolving this problem.

Thanks,

Bob, W5SJS