John W2XS wrote:
the other). If the highest modulating frequency is 5kHz, then the BW of
each sideband will be 5kHz, and the total AM signal will have a BW of 10kHz.
At the receiver, one of the sidebands is discarded, and the other is
demodulated. So, a 6kHz filter should produce a nice sounding AM signal
since a 5kHz-wide signal is passing through it.
If you do that with standard AM (envelope) detection, you will get up
to about 20% (even) harmonic distortion. You will probably get better
audio treating it as SSB, in spite of frequency and phase errors.
To reproduce single sideband full and reduced carrier signals
accurately, you need synchronous detection. (It should also be quieter
for double sideband full carrier.)
(For Scroggie fans, consider the phasor diagram for 100% modulation at
the point where the sideband is at 90 degrees to the carrier. That
gives an amplitude of sqrt(2) when you should just have the nominal
carrier amplitude of 1. At 0 and 180 degrees, you get the expected
amplitudes of 2 and 0.)
--
David Woolley
"The Elecraft list is a forum for the discussion of topics related to
Elecraft products and more general topics related ham radio"
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