There
is a caution to be remembered in this
regard and it has to do with having
two ATUs in the
circuit.
A transceiver
can be used barefoot through the LA-1K
provided the external ATU (HF-AUTO or whatever) is the active ATU
in order to protect the LA-1K.
There have been instances where hams have put
their
external ATU (HF-AUTO or whatever) in OFF or BYPASS, believing
they could then use the
transceiver's internal ATU to do
the matching.
Paul warned against doing this in a similar discussion a year or
so ago, and the caution is printed in the HF-AUTO manual:
Bypass
mode bypasses
the matching network.? Some users have the tuner in
Bypass
allowing them to use their radio’s internal antenna tuner.? Caution is
needed in this last case if
an amplifier is in the circuit and turned off or in
bypass.
The standing waves (SWR)
will potentially have high voltage nodes that can
cause damage to the bypass components in
the amplifier.
In
short, when operating a transceiver barefoot through the
bypassed LA-1K, the operative ATU should remain the external
ATU, not the transceiver's internal one (which should be
disabled).
73,
Kent
K9ZTV
