[Elecraft] Measuring SSB RMS Power

[Don Wilhelm]

John,

That connection is OK if you realize that your scope is reading the DC 
voltage developed by rectifying the RF from 1/2 of the load.  You still 
have to use the power formula that is in the DL1 manual.

I prefer to allow the 'scope to read the full peak RF voltage.  Connect 
the 'scope probe to the side of one resistor which is connected to the 
BNC jack (one of the leads closest to the BNC), and the 'scope ground 
probe to one or the resistor leads furthermost away from from the BNC jack.

Then use the formula to convert peak voltage to power (for a 50 ohm 
load) which is V squared then divided by 400.  Easy to do quickly with a 
handy calculator.

73,
Don W3FPR

On 6/20/2019 9:38 AM, John Oppenheimer wrote:
> Using DL1 with Oscilloscope to measure KX3 SSB RMS power:
> 
> https://www.kn5l.net/ssbpower/
> 
> Question, is this technique correct?
>