|[AMRadio] Web page appears in opposition to RM-11306|
garyschafer at comcast.net
Tue Jan 17 21:08:37 EST 2006
From: amradio-bounces at mailman.qth.net
[mailto:amradio-bounces at mailman.qth.net] On Behalf Of John E. Coleman (ARS
Sent: Tuesday, January 17, 2006 5:11 PM
To: 'Discussion of AM Radio'
Subject: RE: [AMRadio] Web page appears in opposition to RM-11306
As for measure of power, it was 1KW DC
input MAX as measured by the product of plate voltage and plate current
meters with a time constants of .25 sec. As long as the product of the two
meters did not exceed 1KW then you were legal. Typically, when these
conditions were properly monitored, the max output obtainable by a legal SSB
station was about 1500 watts PEP. I jokingly say, "the manufactures of SSB
desktop equipment were sore about the AM stations that could get 750 to 800
watts of carrier and modulate it to 3000 watts PEP output (SINE WAVE) with
out their plate current moving". Not joking, by the use of natural
asymmetrical audio I was able to get about 7 KW PEP output with no plate
current increase. Also there seemed to be a lot of dummying down of folks
about that time.
watts PEP output is about the same as ever for a SSB station but was a kick
in the teeth for big iron home brewers of AM stations.
1500 watts PEP output is not the same as ever for SSB. The SSB guys lost
right along with the AM guys on the maximum power level. At 1 kw average, or
indicated on the plate meter, average output on SSB is around 600 watts. The
PEP level of that much power will range anywhere from 3000 to 5000 watts.
Just the same as it will with AM less of course the difference in amplifier
Watch the output power meter on your SSB rig when it is operated at 100
watts PEP output. The average output (on an average reading wattmeter) will
indicate only around 15 to 20 watts unless you are using lots of compression
or ALC. When not hitting any ALC the average will be quite low.
However in years bygone most people thought that PEP was automatically twice
what average power was. That is true with a two tone test signal but of
course not with voice.
Most amplifiers in those days were not built to deliver much more than 2 kw
pep output so most did not realize what they had lost. A lot of folks
thought they gained power with the new rules as now you could run around
3000 watts input indicated on the plate meter (in CW) for 1500 watts output.
Many were confused about what PEP really was, including the manufacturers if
you look at some of the old spec sheets on SSB gear.
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