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Author Topic: Loggings with CUSB in the title  (Read 2438 times)

Zane

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Loggings with CUSB in the title
« on: October 22, 2025, 2037 UTC »
Recently, I've seen loggings where the modulation is listed as CUSB. Not being familiar with this, the closest explanation I can find is Controlled Envelope Single Sideband. In these loggings, it's Controlled Envelope Upper Side Band (CEUSB or CUSB)?  Is this correct?

For those of us with non-SDR, Fansome approved radios I assume there is no real reception difference. Only the SDR folks would be able to identify the narrower side band?

Is there a tradeoff here? More effective power, but maybe less audio dynamic range?

On edit - I see one of Chris' old loggings showing this as carrier + USB. Is there a technical reason to do this? 

Z

« Last Edit: October 22, 2025, 2045 UTC by Zane »
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Shortwave_Listener

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Re: Loggings with CUSB in the title
« Reply #1 on: October 22, 2025, 2048 UTC »
Carrier + USB. Fully decodable in AM on any normal receiver, also decodable in USB. The only way to tell on a regular radio is switch between AM, USB, and LSB. LSB will have no audio but AM and USB will sound fine. The benefit is mostly just a little less power and bandwidth are used. Some older radios designed primarily for sideband can only generate this instead of AM.

Zane

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Re: Loggings with CUSB in the title
« Reply #2 on: October 22, 2025, 2200 UTC »
Carrier + USB. Fully decodable in AM on any normal receiver, also decodable in USB. The only way to tell on a regular radio is switch between AM, USB, and LSB. LSB will have no audio but AM and USB will sound fine. The benefit is mostly just a little less power and bandwidth are used. Some older radios designed primarily for sideband can only generate this instead of AM.

Thanks much for the clear response.

Z
Palstar R30CC / Sherwood SE-3 MK IV / pa0rdt Mini-Whip / Gone Long Engineering remote resonant loop / Fansome approved

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