Peter Chadwick wrote:
>Actually, the definition of PEP quoted by SM2EKM is the definition in
>ITU-R Recommendation SM328. That definition has been around since the
>1950's.
It is also how "PEP" is legally defined in the US and UK licences, and
probably in many others.
Note that the word "peak" applies to the modulation envelope - NOT the
RF power! Your RF power is defined as the average over one complete RF
cycle, so your PEP is simply the power of the largest RF cycle you ever
transmit.
The audio modulating frequency is much lower than the RF frequency, so
a modulation "peak" will contain at least several hundred RF cycles, all
at the same power level within a fraction of a percent. That gives a
power meter plenty of time to make a measurement... but many so-called
"peak reading" power meters still fail to grab the true peak level of
the modulation.
--
73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek
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