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Old July 4th 07, 08:36 PM posted to rec.radio.amateur.antenna,alt.tv.tech.hdtv
Kadin2048 Kadin2048 is offline
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Default Front-to-back ratio for UHF antenna

In article t,
"Ralph Mowery" wrote:

"Bishoop" wrote in message
(snip)
10 or 12db of forward gain goes NOT equal 10 "times" the received signal
strength.


Then what do you think it is equal to ?



Well, 10dB of gain is a 10x increase in absolute signal, but 12dB of
gain would be about 16x the signal.

dB = 10 * log(S1/S2)
where S1 and S2 are the absolute strengths of two signals you're
finding the dB of difference between.

The regular absolute-value scale and logarithmic scale of dB "cross" at
the factor of 10; so 10dB = 10x, but that's the only place that's true
(at least, I think it is, off the top of my head).

-Kadin.