Page 14 of this pdf says the SSB duty factor used in RF exposure calcs is 
between 20 and 50% depending on compression. I think that’s what you’re looking 
for. 

https://transition.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65b.pdf

> On Jun 16, 2020, at 17:33, David Rowe <[email protected]> wrote:
> 
> Hello List,
> 
> I've been working with Peter, VK3RV on the surprisingly tricky problem
> of measuring FreeDV Tx power.
> 
> Over the weekend I built an inline "sampler" and tried a few averaging
> options to measure the power of a 700D waveform on my spec-an.  I am
> using my IC7200 with the drive adjusted so that the ALC just moves.  I
> am sampling the power between the IC7200 and my ATU, which is connected
> to a dipole on 40M.
> 
> I get 75W peak indicated on two bar-graph type power meters (on the
> radio and ATU).
> 
> Using "power averaging" and a RMS detector on the spec an over about 1
> minute I get about 40dBm (10W).
> 
> The FreeDV waveforms all have a Peak to Average Power Ratio (PAPR or
> crest factor) of around 13dB.
> 
> 1/ Has anyone else tried to measure FreeDV power?
> 2/ Does anyone know what the RMS/average power of SSB is (e.g. for a
> 100W PEP signal)?
> 
> -/-
> 
> Where I am going with this .... 10W is a lot less than say RTTY or PSK31
> typically puts out.  If we can address the PAPR of FreeDV waveforms by
> even 3dB that's signficiant extra link margin.  On the flip side I am
> concerned about blowing up voice-rated SSB PAs with continuous high
> average power levels.
> 
> Thanks,
> David
> <sampler_46dB_sm.jpg>
> <power_700D.png>
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