Andy wrote:
> Just another data point ...
>
> I believe it is standard for AM broadcast stations to match the tower to the
> feedline right at the base of each tower, even with their monster coax or
> when they had balanced open feedline. (I worked at one that still had some
> remnants of their old open feedline runs.)
>
> Work out a loss budget to see how much power you lose by having a high
> feedline SWR.
>
>> Almost everyone recommends matching in the shack as well as at the
>> antenna feedpoint.
>
> You shouldn't need any special matching in the shack if you match correctly
> at the antenna feedpoint. Just a balun with the right ratio.
Or, if you don't happen to have a transformer of the correct ratio, your
in shack tuner can probably do the impedance transformation.
That way, you can choose pretty much any arbitrary impedance for your
open wire line (heck, it can be tapered, and different at the two
ends).. The tuning network at the antenna matches the antenna to
whatever the line is at that end, and your in shack tuner matches your
transmitter to whatever the line is at the shack end.
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