[Elecraft] K3 can now be readily mated to the Yaesu Quadra HF Amp

[Tom Hammond]

Thanks to pinout info from Joe, W4TV, and Kent, K9ZTV, the K3 can now be
fairly easily mated up to the Yaesu Quadra HF Amp.  Joe provided the
main set of pinouts and Kent offered up the key info for getting the
Quadra to go into auto-TUNE mode to allow its ATU to operate when the K3
was Keyed.

K9ZTV is now Field testing the configuration, but so far, things look very
good, and appear to be stable with respect to ALC control of the K3 drive
power. We're still working on getting the Quadra's ALC output voltage level
to that precise setting which will allow the K3 to be run at a drive level
lower than about 80W yet still adequately drive and control the Quadra.
The ALC works nicely, but we'd still like to be able to use about 40W of
drive so the ALC doesn't have to work nearly as hard to control the drive.
I believe we will find the 'sweet spot', but it will probably be a
combination of the K3's EXT ALC setting and the ALC SET value from the
Quadra.

If you would like to see a PDF of the current interconnection illustration,
please drop me an e-mail and I'll send the file to you... can't send PDFs
through the reflector... sorry.

73,

Tom Hammond   N0SS