[Elecraft] K2: Controlling an external amp and tuner

[Owen B. Mehegan]

I'm nearing the completion of my K2 (#6991); I finished phase 2 of the 
RF board this week, completed the alignment, and last night I was able 
to hear some CW on 40m with just 10' of speaker wire as an antenna. 
Hopefully I've have it completely done in the next 1-2 weeks.

I'm already thinking about some possible improvements. I have an 
external tuner and an external amp. I built an RF sense switch for the 
amp which will key it when I'm transmitting, but I still have to 
manually change bands on it. This was fine for my first rig, a 40m-only 
QRP transceiver. But it would be cool if each time I used the Band + 
and Band - buttons on the K2, it changed the band setting on the amp. 
The amp has an input for this, I would just need to build something 
that can trigger it. The question is, how would I trigger this from the 
K2? What's the best way to capture the band change events? Use the 
serial interface? Hard-wire something to the band change buttons?

The tuner might be simpler or might not be. Is there any way I can use 
the Tune button on the front panel to control an external tuner?

Thanks in advance for any insights!

--
Owen B. Mehegan (owen at nerdnetworks.org)
"He is a dangerous mixture of sophistication and recklessness which 
makes one anxious about his influence on other boys."