SSB Transmitter
The single sideband transmitter must perform two functions. These are the
suppression of the carrier wave and the elimination of the unwanted sideband.
The carrier is generated by the carrier oscillator and is on a slightly
different frequency depending on whether upper or lower sideband is chosen.
The carrier is suppressed by feeding the output of the carrier oscillator and
the output of the speech amplifier into the balanced modulator. The output
from this then consists of the two sidebands and the unwanted sideband is then
removed by a crystal filter whith a bandwidth of 2.5 kHz. This is known as the
sideband generator.
The output from the sideband generator cannot be frequency multiplied because
any multiplication would also increase the bandwidth of the sideband and so a
mixer is used to mix the sideband to the power stage.
Click
[ HERE ]
for a detailed diagram of an SSB Transmitter. (This will open a PDF document
in a new window - requires Adobe Acrobat Reader).
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