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Re: [Amps] "10 Meter Ban" to be lifted ...

To: "Gary Schafer" <garyschafer@comcast.net>,"'AMPS'" <amps@contesting.com>
Subject: Re: [Amps] "10 Meter Ban" to be lifted ...
From: "Tom W8JI" <w8ji@w8ji.com>
Date: Sun, 15 Oct 2006 05:17:15 -0400
List-post: <mailto:amps@contesting.com>
> There was no limit on the peak envelope power we were 
> allowed to run; only a
> limit on the average power as read on the plate meters.
>
> Peak envelope power can range from 5 to 10 times or 
> greater than the average
> power we see on the plate meter with voice.

OK, I see your point. Good point Gary and one that almost 
everyone misses.

Conventional thought is the peak to average power ratio is 
only about 2:1. While that may be true for processed speech 
(even through ALC), it isn't true for unprocessed speech.

So technically, using the meter response dictated by early 
FCC rules, we could run 10kW PEP input or more on occasional 
voice waveform peaks without making the meter exceed the 
legal 1000 watts indicated input on suppressed carrier phone 
transmissions.

While the FCC increased carrier mode power like RTTY, FM, 
and CW it decreased peak power and average power of AM and 
peak power of unprocessed or lightly processed SSB.

My only addition to that is the very short duration peak 
doesn't mean much for communications, so we didn't lose much 
in that way (except on AM). Anyone using processing already 
restricted the peak-to-average ratio (which also increases 
communications effectiveness) and would not have seen such a 
dramatic reduction in peak power. In other words the peak 
didn't mean that much anyway when the speech was processed 
to improve communications effectiveness.

Good point Gary.

73 Tom 


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