[Elecraft] Feature wanted for W2 wattmeter

[Vic Rosenthal]

What I want is just forward - reflected. Neglecting losses, this is what the tx is 'delivering'. In real life somewhat less gets to the antenna.

Vic K2VCO /4X6GP 

> On Jan 13, 2015, at 3:19 AM, Fred Jensen <k6dgw at foothill.net> wrote:
> 
> Well ... sort of.  Some of the reflected power heats up the ATU and/or PA depending on the match it sees [actually, some of the forward power does too, tuners have forward losses].  "Delivered Power" is somewhat difficult to calculate.  Working into a matched, non-reactive load [common for AM broadcast, at least a number of years ago], it's "I squared R" where R is the radiation resistance of the antenna ... and some minor conductor losses in the antenna.  Things get pretty sticky if it's not a matched load.
> 
> 73,
> 
> Fred K6DGW
> - Northern California Contest Club
> - CU in the 50th Running of the Cal QSO Party 3-4 Oct 2015
> - www.cqp.org
> 
>> On 1/12/2015 4:46 PM, Phil & Debbie Salas wrote:
>> 
>> 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.
> 
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