usb lsb and ssb

[Twink]

what's the difference between usb, lsb, and ssb?

[Circuit Breaker]

SSB stands for SingleSide Band. LSB stands for Lower Side Band and USB stands for Upper Side Band. SSB is a mode of communication. When you transmit an AM signal, it is composed of three parts - the carrier and two sidebands - upper and lower. The upper and lower sidebands are created by your audio when you talk. In the mid-20th century (maybe even earlier), it was discovered that, by using filters, one sideband and the carrier could be removed. This decreased the amount of bandwidth needed to transmit a message. It also meant that some of the power being used to generate the AM carrier and opposite sideband could then be channeled into one sideband. This is why SSB communications are allowed to use 12 watts instead of four watts for AM. To generate a USB signal, the lower sideband and AM carrier are removed with a high pass filter. To produce a LSB signal, the AM carrier and upper sideband are removed with a low pass filter. When someone refers to SSB, they're referring to either USB or LSB because only one or the other is used for sideband communications on CB. Most english communications happens on LSB with USB comprising mostly of spanish speaking operators.

You can get more detailed information here that might explain it better than I did:
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[madsage]

USB is used above 14mhz and LSB is used below 14mhz everywhere else.
CB radio is mostly used on LSB, I think to be opposite that of standard amateur operation?

But since this is a CB radio forum, what Circuit Breaker said.


933 RiffRaff
in the stickers

[the_junkie]

usb and lsb are what makes up your modulation (I believe)

there is no carrier, and very few watts can really get you heard on ssb

[shooter]

SSB stands for SingleSide Band. LSB stands for Lower Side Band and USB stands for Upper Side Band. SSB is a mode of communication. When you transmit an AM signal, it is composed of three parts - the carrier and two sidebands - upper and lower. The upper and lower sidebands are created by your audio when you talk. In the mid-20th century (maybe even earlier), it was discovered that, by using filters, one sideband and the carrier could be removed. This decreased the amount of bandwidth needed to transmit a message. It also meant that some of the power being used to generate the AM carrier and opposite sideband could then be channeled into one sideband. This is why SSB communications are allowed to use 12 watts instead of four watts for AM. To generate a USB signal, the lower sideband and AM carrier are removed with a high pass filter. To produce a LSB signal, the AM carrier and upper sideband are removed with a low pass filter. When someone refers to SSB, they're referring to either USB or LSB because only one or the other is used for sideband communications on CB. Most english communications happens on LSB with USB comprising mostly of spanish speaking operators.

You can get more detailed information here that might explain it better than I did:
[Please login or register to view this link]

very good explanation . no b.s and easy to understand. you should be a teacher.

[TheCBDoctor]

Hello,

Just a coupe of points about AM versus Sideband. On AM CB you have 4 watts of carrier, as you speak the peak power will go to 12 watts. Since; the carrier makes up half of the power and 25% makes up one of the side bands the AM signal is only 25 % efficient. On side band all of the power is used to do the full legal 12 watts allowed on CB. The noise on receive is half the strength on SSB because its bandwidth is only half that of AM.

There is no percentage of modulation on SSB; as a result interference is kept at a minimum. A 25 watt peak SSB signal will do just as well as a 100 Watt AM signal. Although; sideband is more efficient it is not practical for broadcasting complex signals, such as, music. Can you imagine having to get up every few minutes to adjust the clarifier while listening to music. That is why AM broadcast 550 KHz to 1750 KHz is an AM signal. The fidelity has been improved over the decade because the audio frequency was limited to 5 KHz; it is now 7.5 KHz. It was also expanded from 1600 KHz to 1750 KHz.

After AM music abandoned AM for the much improved FM broadcast system, talk radio has taken over. Stereo has pretty much been abandoned for AM broadcast. Sideband is superior to AM for a number of reasons for simple voice communication. Carrier and one side band is a waste of power, but is needed to make a carrier envelope. On a SSB signal the carrier and the missing sideband is reintroduced at the radio by the receiving radio.

Each radio service has its own rules as to what is accepted for proper transmission on its band. 10 meter Ham allows CW, SSB and FM. CB allows SSB and AM; in Europe FM is allowed. 60 meters Ham allows AM. Each has its power limitations and restrictions on what it can be used for and sometimes why. Ham radio has a gentleman's agreement to not discuss politics. There is a gentleman's agreement to reserve CB channels 36 to 40 for SSB.

When it comes to radios it is all about respecting the other radio bands and what is best for the type of communication being used.

Respectfully

['Doc]

Just some information that doesn't really pertain to CB, so take it for what it's worth.

Most commercial radio systems that use SSB mode use USB. Sort of a standardization thingy. Non-commercial radio, such as ham radio have a slightly different convention. Below 10 Mhz it's LSB. Above 10 Mhz it's USB. Listen to the bands and you'll see that's how it's usually done. Most commercial ham radios are set up like that automatically when you change bands. People who don't conform to that convention cause LOTS of aggravation! There are no 'standards' on CB, no particular established 'method' of which side band to use. The 'conventional' use is very varied. Mostly, it depends on who you are and where you are.
- 'Doc

And just for grins, no FM below 29 Mhz in the USA.

[TheCBDoctor]

Hi Doc

FM is allowed on 10 meter between 29 and 29.6900 MHZ for repeater operation.

[Black Lightning]

I think that's what he said.

[De_Wildfire]

Actually there is USB in use on the low bands below 14 mhz. Control tower, land mobile and Military Affiliate Radio System. But that's for listening use, I guess. On 11 meters, if you hear too much QRM on LSB, you can switch to the Upperside and sometimes the QRM goes away.

['Doc]

'Picky - picky - picky'!
The only time you may hear any other mode except AM on the civilian aviation bands is for over seas flight following. All other civilian aviation radio is AM. If the military uses civilian services it does so on AM. Any other military radio can be almost any mode, sort of, almost never AM.
Why civilian aviation radio is only AM? Basically because you can tell if there are more than one station transmitting at a time and deal with it. That's not possible with FM. Why not SSB? Cause there's no really simple and cheap way to make tuning automatic. You'd get "Donald Ducked" to death (as someone has already said).
The way things are going I expect there to be a lot less AM in commercial use over the next dozen years or so. Just too many 'digital refinements floating around to keep that 'Ancient Modulation' going. Oh well...
- 'Doc

[TheCBDoctor]

Hi Doc

When the S##t hits the fan and all cell phones communication networks, and computers are dead, the only people that will be able to relay what is going on is CB and Ham operators. During 9-11 when all cell phone service was dead, the only way to communicate was by CB and Ham.

I am 50 miles from ground zero and I could see the smoke from my town. Cell phones where useless and even many land lines where overwhelmed. The ancient technology will be what keeps us free. All the new network communications (Trunking) can be control by the government or business (It is hard to tell the difference today)

That is why I do not necessarily condone too much power or talking out of band, it is a good thing to have in an emergency, it is just abused to often for no reason. The CB band is an outlaw band, even though there are plenty of decent people on it, because the government can not control it and free speech.

As long as there are opinions there will always be CB radio and the underground. That is where you will find free speech; although, not always nice speech

Respectfully always,