[Elecraft] Feature wanted for W2 wattmeter

[Vic Rosenthal]

You are implying that I can arbitrarily increase my power output by detuning my antenna!
You are right that reflected power is re-reflected by the source, but there is a sense in which the 'real' power output in my example is 1 kW.

Vic K2VCO /4X6GP 

> On Jan 13, 2015, at 2:46 AM, Phil & Debbie Salas <dpsalas at tx.rr.com> wrote:
> 
> "I would like the W2 wattmeter to be able to display "delivered" power, that is, forward power minus reflected power. This would give a more accurate indication of power going to an antenna when the SWR is not 1:1.  For example, if the SWR on the line is about 2.5 and forward power indicates 1.2 kW, there is about 200 watts reflected power. In that case only about 1 kW (less line losses, of course) is being delivered to the load. It is misleading to look at just forward power."
> 
> Actually, "delivered power" is pretty much what you are measuring. Remember that reflected power is re-reflected by the source and adds back into the forward power.  So in your example, you are transmitting 1200 watts, having 200 watts reflected, then the 200 watts is re-reflected by the source giving you the 1200 watts.  Of course, there will be transmission line SWR-related losses.
> 
> Phil - AD5X
> 
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