Hi Peter,
I'm afraid I've lost sight of the entire argument. I understand now
that this is one of what the ITU and IEC adopted to define peak
envelope power, rather than what can be used to measure peak
envelope power accurately.
> So your own particular definition of PEP is that of a number of cycles.
It is not my "definition" of PEP. It is how measuring the true PEP
works in the real world for the modes we operate.
It doesn't matter how many cycles we read as long as we don't
miss the peak. With a slow envelope rise and fall time, as we have
when the bandwidth is limited by the audio response, we have a lot
of time to charge an energy storage capacitor.
As I pointed out before if the peaks occurred for much shorter
periods of times than indicated earlier, excess power would be the
least of the operator's worries. He would have a signal extending
out either side for many tens or hundreds of kilohertz.
> Now what about the PEP of a ground radar, where they put out a very
> broadband (narrow in time) pulse with rise and fall times of a few pico
> seconds? That's one cycle; and it has a PEP, which is definable by the
> 'power in one cycle' definition.
I'm sorry I'm misleading people. Let me correct that.
If you run a RADAR, be sure to use a scope or a special PEP
meter that responds to the pulse rate correctly.
> The power in one cycle definition is a general one, applicable everywhere.
> That's why the ITU and IEC adopted it.
They should have included a rule about how to measure it, since
common sense in applying the definition to real world systems
seems to be somewhat lacking.
73, Tom W8JI
w8ji@contesting.com
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