Linus via groups.io <colour@...> wrote:
OK. Is that still the case if well formed audio is sent into a qdx, or
will it also have a clicks?
Yes.
QDX is a very clever hack -- it's not a SSB transmitter, where you feed
the well formed audio and the output signal closely resembles it, but it
analyzes the frequency of the input audio signal and produces a single
sine wave, with constant amplitude, based on this frequency.
For example:
- QDX is tuned to 7040 kHz (7040000 Hz)
- audio signal from the computer is 300 Hz
- QDX analyzes the signal and notes its frequency
- QDX adds 7040000 Hz + 300 Hz (working in upper side-band mode) and
determines that it has to produce a tone with frequency of 70400300 Hz
- QDX programs the built-in synthesizer to produce this exact frequency
This is repeated many times per second.
The amplitude of the input signal doesn't correspond to the amplitude of
the output signal.
