[BC] AM Loads

[towers at mre.com]

It is possible the match rotation simply is bad too.  4W dead carrier and
6W with audio is telling.  You should have zero power reflected at DC and
a watt at most with modulation.

  Plot the load AT THE TX CONNECTOR on a Smith Chart and then look at the
rotation and length of the curve. It should be centered at 50-j0. The
longer or more pronouced the curve, or if there is asymetery, the poorer
the bandwidth match. You want to see as short of a curve as possible at
50+/-j0 and an equal balanced curve. And what curve there is, you want
to have it's rotation correspond to the TX's delay.  IIRC, you want the
horns pointed SW for that TX to play nicely.

If it's not 50j-0 at the connector, symetrical, and the curve short, you
need to find out why that's the case before "detuning" the network to make
the TX happy.

MM

> The AM-1A TX output goes through 3/4" foam filled 50 ohm heliax to a
> rocker type antenna switch with the switch output heliax going to the
> ATU input a short distance away.  There is maybe 15' of heliax for the
> whole run from the TX output to the ATU input.
>
> Once the ATU is adjusted for min reflected things run fine so I doubt
> that I have a coax problem.  I have about 4 W reflected CW and about 6
> W with full modulation.
>
> Ron D
>