Lower single sideband - Sideband - Wikipedia


Most voice signals on HF are SSB, so you have to choose between USB upper sideband (USB) and lower sideband (LSB). The actual SSB signals extend in a narrow band above (USB) or below (LSB) the carrier frequency displayed on the radio.

Even with a SSB receiver there is some leakage – the unwanted sideband is typically attenuated with a factor of of 10 – 50. Thus if looking for a line at GHz with HARP it would be unwise to use the lower sideband (LSB). The strong 12 CO line at GHz would be in the upper unwanted sideband. Even if HARP is a SSB receiver the CO line is frequently brighter than 20 K so you can still see some remnants of the CO line. Thus care has to be taken when selecting sidebands even for a SSB receiver.


Lower single sideband

Lower single sideband