[Elecraft] K2/KPA100 vs. EC2/KPA100

[Robert Johansen]

Hi Greg,

Congratulations on building  K2  S/N 6100.

I built the EC2/KPA100/KAT100. The rig operates the same as if the KPA100
was installed in the K2.

It is a great feature to be able to quickly disconnect the K2 from the
EC2/KPA100/KAT100 to take just the K2 to the field for outside QRP
operation. I have the KAT2,  Battery option and auxiliary interface built
in the K2 cover.

There are excellent instructions posted  by Lyle KK7P and  John KI6WX on
the Internet to show how it is done.

When the EC2/KPA100/KAT100 is attached to the K2 and  the power level is
set below 11 Watts the amplifier is bypassed and goes through the KAT100
for tuning.

The KAT100 shows this mode the Low power indicator led is on.

As Don W3FPR  suggested, it is best to build and complete the K2 and
KPA100 together and when all tests are complete separate the KPA100 to
prepare it for installation in the EC2.

I decided to build my own auxiliary interface from ideas posted by KK7P
and KI6WX  to do this without the KIO2 since I  did not need the RS-232
function because I was not interested in connecting the K2 to a computer.


The only consideration is that if you do not have the KAT2 you may need a
QRP antenna tuner for field use if you do not operate into a resonant
antenna with a 50 Ohm load.

GL  73,

Bob Johansen WB2SRF  K2  S/N 5622