>
>Fisher wrote:
>>>
>>> <For the FCC PEP rule, Part 97.3 defines PEP as "The average power
>>supplied
>>> to the antenna transmission line by a transmitter during one RF cycle at
>>the
>>> crest of the modulation envelope taken under normal operating
>>conditions.">
>
>>The problem to me is not that it is or is not picky - it is that I don't
>>know what they mean. Once I know what they mean, then I'll know if it is
>>picky or not. What do they mean?
>>
>
>The FCC quote is complete, accurate and consistent. It's also the same
>definition as is used in the UK.
>
>Just remember that the "Peak" in PEP means the peak of the *modulation*
>- not the peak of the RF cycle.
>
>Your RF power is always defined as the average over one complete RF
>cycle (or several complete identical cycles). That's what the "RMS"
>operation does.
>
Indeed. PEP is not peak power, it is RMS power at the modulation peak.
IOW, the limit is effectively 3000w peak, which is 3300w-p with the 10%
FCC allowance. For those who are intent on exceeding the speed limit,
use an old-time tank with a swinging link feeding ladder line. I know a
guy in LA who runs such a cludge. He got inspected by the FCC. They
brought their Bird deluxe 50-ohm stuff and threw up their hands. Sorry,
Charlie. They estimated his power at 'around a kilowatt', thanked him,
and promptly left. From on-the-air shootouts, my guess is that he was
running roughly 3 out. He was using every bit of a 5v, 100a fil.
transformer when he had all four tubes plugged in. .
>The only difference with "PEP" is that it's saying, in effect: "Identify
>the largest, most powerful RF cycle at any time in your transmission -
>that's the one the power limit applies to."
>
>For practical amateur modulation modes, the modulation frequency is
>thousands to millions of times slower than the RF frequency.
? good point
cheers, Ian
- Rich..., 805.386.3734, www.vcnet.com/measures.
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