On Fri, Sep 1, 2023 at 10:08 PM, Colin Kaminski wrote:
I may have a simplistic view, and I hope to be corrected, but it seems to me that an EER method can only reproduce a single tone at a time. The code tracks the loudest frequency and duplicates. The wave shaping circuit changes the volume. ?This can not generate a true two tone signal.?
If you look in the audio domain, you have a two (or multi) tone signal. ?However in the RF domain, you see close to an almost pure single frequency RF waveform with nearly invisible frequency changes (on the 20M band, SSB modulation only changes the RF frequency by 2.5kHz/14MHz or a max of 0.02% change). ?Those changes are very slow (audio rate) compared to the RF frequency, but can include an array of many microscopic sidebands, a lot more than just two. ?So you can change a narrow-band close--to-pure RF waveform in amplitude and phase by tiny amounts at a relatively slow rate, and end up with tons of audio frequencies when those tiny-at-RF sidebands are modulated back down to baseband, where they now become large differences relative to each other in terms of rich audio.
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73, Ron, n6ywu
