there is no such thing as rms power. rms is a term that deals with currents and voltages measured to determine cw or average power. advertisers picked up on this term back in the late 70's under IHF A202 when the term was used simply as extreme shorthand for power in watts calculated from measuring the RMS Voltage. (RMS is validly used in this context) in stereo equipment, no less. the guy who mistakenly translated this confusion into the radio-communications electronics arena should be soundly thrashed.
the line of Bird wattmeters that we are all familiar with measure power in Continuous Sinusoidal Wave, CW for short or better understood as average power. (excluding the 4300-400 Peak Power Measurement Modification Kit)
The confusion in terminology comes because the nominated amplifier load for the measurement is nearly always purely resistive. For this case (only), the measured average power is proportional to the MS [mean square--ed] current or voltage (not RMS) or is (exactly) equal to RMS current times RMS voltage. But the figure resulting from this calculation is not RMS power!
let's hit that again....RMS Current multiplied by RMS Voltage equals measured Average Power.
By contrast, RMS (root mean square) power, (if there was such a thing) would have to be defined as the square root of the time average of the square of the instantaneous power, since this is what 'RMS' means. This could be done, but it is not the power as measured, and furthermore, it would have no technical significance (e.g. it doesn't measure heating power).
In a properly-adjusted AM transmitter, average power at 100% modulation = 1.5 X resting carrier power, and PEP = 4 X resting carrier power. (as was loosely alluded to previously)
In SSB, depending on voice characteristics, average power may run 50% to 65% of PEP.
now, your question........
When you don't have a meter that reads PEP on sideband is it possible to convert the rms readings to give an indication of PEP.
what are you measuring for average power presently and what radio are we talking about?
</p>Edited by: <A HREF=http://p067.ezboard.com/bworldwidecbradioclub.showUserPublicProfile?gid=freecell>freecell</A> at: 6/7/04 11:14 am