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Using Exalted Carrier Single Sideband
This technique (often abbreviated ECSS) depends on the receiver's selectivity as well as being able to select one sideband or the other.
The basic procedure involves tuning an AM signal in sideband mode. Tune it until the signal has no tone on it (this is referred to as zero beating the signal) This generates 2 signals - one lower than the the original frequency, one higher. Either using the BFO or a synchronous detector, you tune away from the interference by selecting one sideband or the other. You would then use other controls (if available) to further clean up the signal. Tuning like this can be reported as ECSS-U if you were listening on the upper sideband, or ECSS-L if listening on the lower.
Note that another definition of ECSS is Exalted Carrier Single Signal.
Are there any radios that can do this today?
Most any radio that can tune USB or LSB could potentially use ECSS. The key is how much the opposite sideband is being rejected. The higher the rejection, the better the results.
There are several factors that can influence a radio will perform using ECSS. Frequency stability - the radio doesn't drift off frequency - is important. But even more important are any available selectivity enhancing tools such as multiple bandwidths that can be selected independently of mode (for example, the Tecsun PL-880 has 5 bandwidths available in sideband mode), passband tuning (which allows one to 'slide' the IF by a khz or two) and various kinds of notch filtering (found on Drake model radios, for example) are all tools that you can use to enhance the audio when using ECSS.
In the world of Software Defined Radios (SDRs) the following applications are known to support ECSS. If there are others not listed here please feel free to add them;
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