[Elecraft] KPA 500 and FTDX 3000

[j-meister at comcast.net]

For the person who asked.... 

I used the 15 pin Linear jack on the back of the FTDX-3000 to accomplish a few things. First of all, I used Yaesu pin 2 (TX GND) as 
the key line for the KPA500, rather than the Elecraft's separate phono cable. Secondly, I used Yaesu pins 4, 5, 6 and 7 to supply the band 
data to the amplifier rather than rely totally on the KPA500's auto-sense of the frequency. And, of course, pin 3 is the common 
ground for all of this. At least on the FTDX-3000, ignore the KPA500's instructions about Yaesu pin 8 (TX INH) - just leave it alone. 

Also, I used Yaesu pin 11 (TX REQ), and ground, out to a separate push-button switch. When pressed, this forces the FTDX-3000 
into a CW carrier (regardless of current mode), and I've set the menu #178 to let it output only 10 watts. 

So in use, I put the KPA500 to operate, press my little push-button switch which puts 10 watts out to the KPA500, which then generates 
about 200 watts into my tuner, which I quickly adjust if necessary. Let go of my push-button switch, and I'm good to go with about 
25-30 watts preset on the FTDX-3000 power. 

Jim, K2WU