>
>> Now either I have one hell of an efficient HW 101, to get 200 watts
>> out with 45 watts input, or there is a flaw in this business that the
>> directional watt meter reads properly at all impedance's. Yes the net
>> power delivered to the load is zero as the meter would show
>> subtracting reflected from forward. However I would conclude that
>> there is not 200 watts forward power and 200 watts reflected on the
>> line.
>
>Not really.
>
>If you subtract the reflected power from the forward power, you get
>the true power delivered to the load.
>
? True power is measured with a bomb-calorimeter. An NBS-traceable
calibrated o'scope measurement of RF potential across a known, matched,
termination comes in second -- and it takes <1% as much time to make a
power measurement as it took in my college physics lab using a
bomb-calorimeter.
- I used to work in a metrology lab and we calibrated wattmeters using
a calibrated o'scope and an accurate termination.
>...
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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