rjr@mgweed.UUCP (09/27/83)
I have a question on the new FCC rule regarding PEP power measurement. It seems to me the wording is aufully confusing on their definition of what PEP is. I don't have the text of the Report & Order in front of me, but in the same sentence they talk about "average", "crest" and "peak". To me, PEP is not an average power but the instantaneous peak at the crest (highest value) of the cycle. How does the word "average" get into this?????????? Bob K9EUI
michaelk@tekmdp.UUCP (Michael Kersenbrock) (09/28/83)
The power rule, as I would interpret it (not necessarily the same way as the FCC) is that they are talking about peak average power, NOT peak-instantaneous power. The hint of this is the "E" in PEP. It is peak ENVELOPE power. The envelope is in that viewpoint of the waveform where the signal is going up-and-down at the *audio* rate, not the 14 Mhz up-and-downing. It is this envelope that is 4x carrier power on AM. "At" the peak of the envelope, you have MANY 14 Mhz cycles, and it it the average power of this level (not peak instantaneous) that is being specified. So you have (Erms)(Erms)/(Rant) =< 1500 Watts where Erms is at the peak of the *envelope*. In the case of cw, the "peak" of the envelope is when the key is down. Mike Kersenbrock WB4IOJ Tektronix Microcomputer Development Products Aloha, Oregon