The generated power is the drawn energy multiplied by the amplifier
efficiency factor, the delivered power
is instead the energy effectively transfered to the load.
In a mismatched condition, expecially were readings are done with indirect
instruments like power meters that read a voltage at a stated impedance
(which is not if SWR is high), the effective tranfered power is not so
easily determinable. The algebrical sum of direct and reflected voltage,
roughly correct as a relative reading and to determine VSWR, could be wrong
in the read power absolute numbers.
If I were an officer to check the used power in your station and rules are
relative to the antenna feed point (I don't think so), or I bring the meter
to the antenna feed point (but looks quite impractical), or I will ask you
to tune your amp into a dummy load without changing the drive power. Fixed
this point, if allowed power is really relative to the antenna feed point
(an E.R.P. would have more sense) and not to the transmitter, losses "along
the way" can be taken in account and compliance verifyed.
73,
Mauri I4JMY
-----Messaggio Originale-----
Da: Jon Ogden <jono@enteract.com>
A: Jim Reid <jreid@aloha.net>; Amps Reflector <amps@contesting.com>
Data invio: giovedì 30 settembre 1999 6.26
Oggetto: Re: [AMPS] Reading Reflected and True (?) Power
>
> Jim Reid wrote:
>
> >Oops, forgot one question within:
> >
> >> >Jim Reid wrote:
> >
> >some stuff and some questions..
> >
> >4. How much power is the linear actually generating?
> > About 1500 or about 1800 watts?
>
> 1500 Watts. The power meter in reading total power is reading
> effectively the sum of forward and reflected power.
>
> 73,
>
> Jon
> KE9NA
>
>
> -------------------------------------
> Jon Ogden
> KE9NA
>
> http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
>
>
> "A life lived in fear is a life half lived."
>
>
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