can anyone help me???

Thread Starter

dakanat

Joined Nov 12, 2008
25
hello'


How i can transmitting one message signal in the upper sideband of an AM carrier and a different signal in its lower sideband?
 

KL7AJ

Joined Nov 4, 2008
2,208
You're talking about an independent sideband (ISB) transmitter. This can be done fairly easily with DSP I/Q phasing techniques. However, I don't know of any commercial amateur transceivers that do ISB. A while back there were some military radios that did that.

Are you looking for info on how to design this...or how to practially do it?

Eric
 

Thread Starter

dakanat

Joined Nov 12, 2008
25
yes i do i need more info about
Actually
full info about it if u can Plz

Dakanat
 

KL7AJ

Joined Nov 4, 2008
2,208
yes i do i need more info about
Actually
full info about it if u can Plz

Dakanat
Hi, Dakanat


I'll fire up the old ICAP4 program and put together a block diagram for you....the OLD FASHIONED phasing method. If you want to do it in DSP, your best bet is to get a copy of the ARRL handbook and see how SSB is genereated digitally.

eric
 

KL7AJ

Joined Nov 4, 2008
2,208
whats ARRL handbook ???

Do u have all opration?

thankssssss

Here are two formats for my ISB generator. The toughest part of the project is the design of the 90 degree audio phasing networks. It was a real challenge to build networkds that have a 90 degree phase shift over the entire audio spectrum (about a 10:1 frequency ratio). This is largely why the phasing method fell into disuse a few decades ago...but is now popular again, because of DSP methods.

The ARRL Handbook is the standard reference book for Amateur Radio. You can get it from the American Radio Relay League (www.arrl.org)

Eric
 

KL7AJ

Joined Nov 4, 2008
2,208
thanks Eric
You're most welcome. By the way, ISB was used in the ill-fated Kahn-Hazeltine method of A.M. Stereo. It was a good system, but beset by politics...and the FCC never adopted a workable AM stereo system.

eric
 
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