Quoting Donald Fox via Amps <amps@contesting.com>:
Gents:
So, if WLW ran the "old school" way of modulation, and had at one
time an actual 500 KW carrier, would their meters have stood at 500
kw steady, or hung around 125 KW with 0 modulation and then swung up
to 500 from there?
Great Question.
WLW was licensed for 500KW ( 1/2 Megawatts ). Their *Peak* power
would have been 2 Megawatts at 100% modulation. With a steady state
audio tone, again at 100% modulation, the positive peaks would be
offset by the negative peaks on a slow-to-respond meter and the
average power would have shown 500KW and the slow meter would have
indicated no movement up or down from carrier power.
BUT........ looking at the carrier with a fast acting oscilloscope
would show a voltage increase from carrier levels to 2 x carrier level.
Twice the voltage into the same resistance ( antenna ) = twice the current
voltage doubled times current doubled = 4 times power. ( peak ) 2 Megawatts
Current ham transmitters capable of 100 watts peak SSB can work on AM
by insuring that your carrier ( no modulation ) doesn't exceed 25 watts.
Keep the mike audio at or below ALC threshold and you should have a
clean AM signal.
Don W4DNR
DonR
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