Cobra 25LTD Classic tune up
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The carrier in Double Sideband Full Carrier Amplitude Modulation
should remain constant during modulation. If not, then you have a far
greater problem.
james
Hello James:
No thats not how AM works. The Modulation increases and decreses the
amptitude during Modulation. Thats how double sidband full modulation
works. Look in a old ARRL Book.
Jay in the Mojave
Jay, I respectfully disagree.
An AM carrier doesn't change, just sidebands are added in the mixing (modulation)
process, and the instantaneous voltage shown on an o-scope will be 4 times greater
then the carrier power itself. Since the audio added is 50% of the carrier, the
RMS power will be 150% of the unmodulated carrier. The peak to peak voltage is
greater. Put a 1000 Hz tone on a signal and look at it on spec-an.
(make sure to do this test with an unmodified radio, "swing kits" ruin proper AM)
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