[Elecraft] Feature wanted for W2 wattmeter

[Vic Rosenthal]

Here is an experiment to show what I mean.
Take a transmitter and connect it to a 50 ohm dummy load through an antenna tuner. Put a wattmeter between the transmitter and the tuner.
Now adjust the transmitter for 100 watts output and the tuner for 1:1 SWR. 
The meter reads 100W forward and zero reflected power.
Now adjust the tuner for an SWR of about 2.5:1. The wattmeter will show forward power of about  120 watts and reflected power of about 20 watts. Did I increase the real power output of my transmitter? Did I make my signal stronger? No.
I want a wattmeter that has an option to indicate 100 watts in this situation.

Vic K2VCO /4X6GP 

> On Jan 13, 2015, at 6:56 AM, Walter Underwood <wunder at wunderwood.org> wrote:
> 
> No. That is wrong. Forward and reflected are aspects of the standing wave, not power delivered. —wunder, K6WRU
> 
>> On Jan 12, 2015, at 8:53 PM, Vic Rosenthal <k2vco.vic at gmail.com> wrote:
>> 
>> 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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