Why not just calibrate a Trapezoid display for MAXIMUM PEP? The just watch the trapezoid display?
Watching a single cycle on a scope is a difficult thing to do. HOW DO YOU AVERAGE PEP ON A SINGLE CYCLE? Bob Macklin K5MYJ Seattle, Wa, "Real Radios Glow in the Dark" ----- Original Message ----- From: "John Coleman" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]>; "'Discussion of AM Radio in the Amateur Service'" <amradio@mailman.qth.net> Sent: Thursday, February 14, 2008 1:55 PM Subject: RE: [AMRadio] Modulation power required Perfectly and beautifully said Gary, except for one thing and some may not have caught it. I make this sort of mistake all the time so I'm glad I'm not the only one, HIHI. I hope you don't mind my adding in a little here just for clearing up a little detail. Original paragraph said: "Well, PEP is defined as the AVERAGE power over at least one audio envelope cycle. So we need to use the average power of the carrier at least. Average power is derived from RMS voltage so we use the RMS voltage of the carrier." The above statement is defining the average power over one audio cycle would be the 2 sidebands power plus the carrier power as you said before. For PEP it should read: "Well, PEP is defined as the AVERAGE power over at least one RF cycle at the most powerful point of the envelope." I have been asked this so many times so I feel compelled to expand on it. While looking at a envelope display on the scope and picking a place on the screen where the envelope is at the tallest peak then expand your scope horizontally to a mile wide display so as to see one or two RF wave forms at the place where the envelope peak was and measure the average power of the one or two RF waves at that point. Since we can't expand the scope to a mile wide display we must calculate the values as Gary said and imagine what we might see. John, WA5BXO ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/amradio@mailman.qth.net/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
