Jim Reid wrote:
>In either case, the radiated peak power is at the legal limit, I
>presume. If the first supposition is true, the output circuit
>does what a tuner would do; that is, re-reflect the power
>originally reflected at the line/antenna terminal; and in the
>second, the linear dissipates the reflected power as heat.
WOW! You are asking some tough questions here!
First of all, indicated forward power is likely to be the SUM of the
forward and reflected power. One way to check is to tune the amp into
your antenna. Then with the same level of drive, tune it into a 50 Ohm
dummy load. It should come quite close to verifying that.
OK, regarding reflected power: The likely scenario is that some of the
reflected 305 watts IS indeed absorbed at the amplifier and effectively
becomes heat. However, unless the output of your PA looks like 50 + j0
Ohms, you won't absorb all of that reflected power. Some of that 305
Watts will be reflected back towards the antenna. And so forth and so on.
The bottom line is that you ARE legal. No problems there. Your true
forward power is 1500 Watts or nearly so.
Now, here's another one for you: You can run more than 1500 Watts in the
shack. The rules refer to 1500 Watts AT the antenna terminals. So if
you have some loss in your long run of coax, you can compensate inside
the shack.
73,
Jon
KE9NA
--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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