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Old May 2nd 08, 05:11 PM posted to rec.radio.amateur.antenna
Richard Harrison Richard Harrison is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 588
Default Disadvantages of using AM for DSSS/FHSS Spread Spectrum?

Frank, GM0CZ / KN6WH wrote:
"It is sometimes even possible to open the Boston, Mass. repeater on
29.600 MHz."

FM is almost essential to repeater operation due to the inherent
automatic gain control of the FM mode. Once the weak signal point called
the "FM improvement threshold" is exceeded, further carrier strength
increases have no effect on the recovered modulation. The pip squeak is
as loud as the power house. Remodulate that on the repeater output.

Best regards, Richard Harrison, KB5WZI