[Elecraft] Transmit when switching from DATA to AM mode?

[John Buck]

I confirmed on K3 #125 with V 2.76, the behavior described by KB8AP below.
I also noted that the power supply jumps up to the level expected for 
the power setting.
So I believe that it is attempting to transmit during the second or so 
of the transient.
This is not a good thing.  I do not have a 6 kHz filter installed.

John KH7T

Hi all,

I've just discovered something odd with my K3 (#1772).  When I switch 
mode from DATA to AM via the front panel Mode button, the rig tries to 
transmit.  The red TX light comes on momentarily and I get a ERR TXF 
message (if in band) or an END message (if out of band) in the VFO B 
area.  I don't have the AM filter installed, so I don't think anything 
is actually going out over the air, but it doesn't seem like the rig 
should ever go into transmit on a mere mode change.

It ONLY happens when going from DATA to AM, not when going from FM to AM 
or between any other modes in either direction.  There is no mic 
connected to the rig, nor anything connected to the rear panel mic or 
line inputs.  The only things connected to the rig are a paddle, an 
external speaker, and the antenna.   It happens whether in VOX or PTT mode.

I first noticed it with MCU 2.67 (although I can't say if it happened 
with earlier versions.)  I've updated to the 2.76 beta release and it 
still happens.

Anyone else see this?

73
-- 
Joe KB8AP