On 8/27/2010 8:18 PM, wb6dgn wrote: > > If you reduce the modulation without reducing the receiver bandwidth, then, > yes, the range will be reduced. You have reduced the signal without also > reducing the noise. However, if you reduce the modulation and, at the same > time, reduce the receiver bandwidth and audio recovery, by a like amount, > then I do not see how the signal:noise ratio, and therefore range, would > change appreciably. Relationships aren't linear, or you'd be right. Reducing the modulation index and simultaneously reducing the receiver bandwidth from 5 to 2.5 kHz results in a situation which requires ~6 db more signal level for the same demodulated quality (ex. 12db SINAD)
Matthew Kaufman
