Dan Zimmerman N3OX wrote:
> All 1 sunit. It just doesn't seem linear...Not worth the extra $ to take
>> down a tribander that has maybe 4dbd gain on 20mtrs for a huge mono band
>> yagi with a 32' boom and truss supports for the boom ect for a mere 3.5 db
>> gain. Maybe im missing something here.
>>
>
> Tony,
>
> When DX signals are about even with the noise, and the noise and DX signal
> are steady, a good set of DXer ears may be able to just detect a 1dB change.
1 dB is basically one "just noticeable difference" in levels for sounds
in general (and for most stimuli.. google Weber-Fechner...)
>
> 3.5dB might actually be a really useful amount of signal level. It's
> certainly not worthless to add 3.5dB gain to your antenna system, even if it
> requires a lot of planning and assistance from TowerTalk (that's why this is
> topical, right?)
>
> And if a S-unit is 6dB, that certainly matters. I did a rough little
> experiment in a sound editing program:
>
> http://www.n3ox.net/files/6dB
>
6dB is a doubling of voltage, for what it's worth...
AND, the S-meter was traditionally hooked to the AGC line, so it really
displays whatever the AGC detector produces. Most semiconductor diode
RF detectors are roughly square law (voltage proportional to power), so
a dB/volt curve makes sense. I don't know about thermionic diode
detector characteristics...
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