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3dB loss from 2:1 SWR
I know the actual lose from a swr of 2 is only 0.5 dB but the digital signal is more
fragile to the effects of high swr than old analog signals were, due to error
vector magnitude high swr can render a signal unwatchable.
And even moderate swr of 2 can raise the "effective noise factor" by at least 3 dB
with regard to a digital signal.
That's half the signal or twice the noise depending on how you look at it.
So well designed /engineered antennas work the same as they ever did.
Also old antennas (and some new but old design) may be designed to peak at
channels above what are now used.
All you uber-gurus out there.
If any one can show how to calculate this effective increase in noise
factor for any given swr It would be greatly appreciated
Last edited by ghz24; 9-Dec-2011 at 6:50 PM.
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