Single Sideband (SSB) is the standard mode of voice communication for HF operation in Amateur Radio across the globe.
It was used for Intercontinental Telephone communication long before it found its way into Amateur Radio (1923).
In this video I will help you understand the How and Why of Single Sideband communication both on the Transmit side and the Receive side.
I start with its foundation in the world of Amplitude Modulated Phone and how it evolved into modern Single Sideband.

When you look at the spectral content of the AM and the DSB Suppressed Carrier signals, you will notice that there are multiple sideband pips at 1xModulating Frequency, Fm, 2xFm, 3xFm, etc. away from the carrier.
It turns out that the pips at 2xFm and above are due to distortion of the audio, not the "ideal" signal. I discovered this through the mathematical investigation into the "ideal" AM signal which only contains the carrier, Fc, and one sideband pip at Fm away from the carrier on either side of the Fc, carrier.
Furthermore, the real world mixer is not necessarily linear. This fact also adds to the additional sideband pips (and the F1 +/- (F2*n) reality).
If you are interested in playing with this, I've provided the link to my GNU Octave file, below.

I have provided a link to a very interesting video on the history of Single Sideband in the promised links, below. It is 47 minutes long, but contains a lot of cool information. The presenter is Ed Gable (no relation of mine).

Promised Links:
AM, LSB and USB Spectral Content Compared (IC-7610 experiment) Spreadsheet
https://drive.google.com/file/d/1eNx9...

GNU Octave Simulation & Frequency Content of an Ideal AM Signal
https://drive.google.com/file/d/1gKzN...

The History of Single Sideband (Antique Wireless Museum)
   • The History of Single Sideband  

Time Markers for Your Convenience
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00:05 Introductory Comments
01:10 Amplitude Modulation, S.S.B.'s foundation
01:29 Definition of Terms
01:38 Modulation
02:03 Carrier
02:49 What is Amplitude Modulation?
02:57 Amplitude
03:25 A.M. Demo-Introduction
03:59 Time Domain
04:37 Frequency Domain
05:48 Double Sideband, Suppressed Carrier: Introduction
06:56 Generating the Signal
09:27 DEMO: The Tour of the Hardware
10:14 Time Domain
10:50 Frequency Domain
11:44 Single Sideband: Introduction
12:19 A Little Amazing History
13:07 How do we generate the signal?
14:28 Receiving SSB: Introduction
15:07 How do we do that?
15:10 Carrier Injection
15:58 The Product Detector
17:07 Final Comments and Toodle-Oots
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