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Old 15th August 2001 | 15:28
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Don D Cake
 
Joined: Nov 2000
Posts: 120
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From: St Albans, herts, UK
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Re the SSB question.

When you mix signals (and that's all you do when you AM modulate), say Fc and Fm you end up with Fc, Fm, Fc + Fm, Fc - Fm and Fm - Fc.

So in a double side band transmitter with a carrier of 10MHz (Fc) and a modulation frequency of 10kHz (Fm) you would transmit the carrier frequency (Fc) and two side bands (Fc + Fm and Fc - Fm). The modulation frequency (Fm) would be filtered out and Fm - Fc is a negative value so it can't exist. That is you would transmit three discreet signals, 9.99MHz, 10MHz and 10.01MHz.

It is inefficient to transmit all this stuff so you can get away with transmitting one side band only and use a regenerative receiver with a local oscillator. This type of transmission is called Single Side Band Suppressed Carrier.

This is where your question is vague, you have to make some assumptions. You have to assume that the carrier is suppressed and that the side band transmitted is the upper one. In this case the answer would be 10.01MHz. If the lower side band is used the answer would be 9.99MHz.
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