[Elecraft] P3TXMON question?

[Alan Bloom]

The narrow bar is PEP (peak envelope power) with a long time constant. 
The solid bar is effectively also PEP, but with a shorter time constant 
so you can see what the modulation/keying is doing.

By the way, in the radio industry, the term "peak" is used in more than 
one sense, which can be confusing.  PEP is the peak of the transmitted 
power, which is computed from the RMS value of the RF voltage, not the 
peak value.

For example, on an oscilloscope display you see the peaks of the sine 
waves, which are sqrt(2) = 1.414 times the RMS voltage.  To use an 
oscilloscope to measure RF power (PEP or average) you have to divide the 
peak voltage by sqrt(2) before using the formula P = E^2 / R.

Alan N1AL


On 08/21/2015 08:43 AM, Chester Alderman wrote:
> Mke....
>
> I am not absolutely sure about this, but on page 29 of the Rev. E, July
> 14,2015 'High Performance Panadapter' manual, in the second column it states
> "The power output bar graph shows both the current power with the moving bar
> and the peak power achieved with a narrow bar." The insinuation is the
> 'moving bar' indicates RMS power and then states that the single narrow bar
> indicates 'peak' power?  Hopefully Elecraft will soon clarify this for us.
>
> 73,
> Tom - W4BQF