> There was no limit on the peak envelope power we were
> allowed to run; only a
> limit on the average power as read on the plate meters.
>
> Peak envelope power can range from 5 to 10 times or
> greater than the average
> power we see on the plate meter with voice.
OK, I see your point. Good point Gary and one that almost
everyone misses.
Conventional thought is the peak to average power ratio is
only about 2:1. While that may be true for processed speech
(even through ALC), it isn't true for unprocessed speech.
So technically, using the meter response dictated by early
FCC rules, we could run 10kW PEP input or more on occasional
voice waveform peaks without making the meter exceed the
legal 1000 watts indicated input on suppressed carrier phone
transmissions.
While the FCC increased carrier mode power like RTTY, FM,
and CW it decreased peak power and average power of AM and
peak power of unprocessed or lightly processed SSB.
My only addition to that is the very short duration peak
doesn't mean much for communications, so we didn't lose much
in that way (except on AM). Anyone using processing already
restricted the peak-to-average ratio (which also increases
communications effectiveness) and would not have seen such a
dramatic reduction in peak power. In other words the peak
didn't mean that much anyway when the speech was processed
to improve communications effectiveness.
Good point Gary.
73 Tom
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