The KX3 has a single BNC antenna connector output for HF. The KX3-2m
transverter is to have a separate sma antenna connector. In both
cases it appears that one will need an interface between the KX3 and
This unit uses either RF sensing or a TR control line from the 28-MHz
IF radio to control transmit/receive switching. The unit will take
up to 25w input and reduce that to as low as 10mw or as high as 1w
for driving the transverter thru a separate Tx coax line. The unit
has a separate Rx coax line for connection to the
transverter. Signal loss from transverter to 28-MHz IF is less than
1-dB in receive.
Its operation is functionally the same as the KXV3 for interfacing
transverters and will work with any HF SSB radio with 25w or less
output. One could HB this but you probably would not save much over
the AOS-28. There is an identical unit (AOS-144) for interfacing 2m
IF radios to transverters that use 2m input.
These two units are fully assembled and not offered as kits by
DEMI. You should specify the transmit drive level you want for your
transverter when you order as it will be setup at that level for you.
I know nothing about Tx delay availability on the KX3. One should
not need any antenna tuner for interfacing a transverter. I assume
the KXAT3 has a bypass mode.
Until the KX3-2m is available I have an older DEMI 144-28 transverter
I recently modified to work with the KX3, when it arrives. It has
the circuitry that the AOS-28 supplies so one can just connect the
KX3 to the transverter. This transverter is no longer made by
DEMI. PS: I have no financial connection with DEMI.