[Elecraft] KX3 s/n 1965 on the air - and a power-up question

[Michael Aiello]

I'm very excited to get my new KX3 on the air, and during my initial
exploration of the rig, I discovered something unexpected. It appears
that the rig will not power on if there is no antenna attached. I
noticed this first when I disconnected the coax to change the antenna
setup while the rig was on and in receive mode  - the rig immediately
shut down. Then with the antenna disconnected I tried to power up - no
response. After reconnecting the antenna, everything behaved normally.

I did not find any mention of this in the manual. I don't have an ATU
installed, perhaps that might have an effect.

I am running from an external 20A power supply (a venerable TenTec
252M), and the load is RG 8X connected to an LDG Z-11 autotuner,
feeding an outdoor dipole.

If this is normal behavior, does it have implications for doing
firmware updates? Must the rig have some kind of load attached in
order to power on to connect to the computer?

In all other respects everything is working fine and I am very pleased
with the rig. My first CW contact was Bulgaria on 10w from the east
coast!

73
Mike N2HTT