Stepping aside from the enlightening discussion on tube gain vs. plate
voltage, I want to come back to the original poster's question of why his
peak power meter read differently at CW than at SSB.
I don't know why I didn't think of this before, but I remembered some
stuff from when I had my engineering days.
We used HP power meters in our labs and with one CW tone (say at 5 dBm),
the meter would read one power level. If two tones were measured such
that the total power out was stil the same (each tone would be 2 dBm -
half the power of 5 dBm), the meter would read differently (I forget
wether it read higher or lower - I think it was lower). This is due to
the way in which the envelope of the signal is detected. Note: These
were VERY expensive power meters.
An SSB signal is in effect a much broader signal (than a CW signal)
almost equivalent of a multi-tone environment. The envelope detection
circuitry on the power meter just might not be able to do a good job of
detecting peak power that is broader than a CW signal.
IMHO, the best way to read the actual peak power is to read it with a CW
signal. This is what I always did in my design days.
73,
Jon
KE9NA
--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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