clvrmnky wrote:
A good receiver actually gives you
TONS of information. You can hear overmodulation,
sideband "splatter" to adjacent channels,
spurious oscillations on other channels,
dead carrier hum in your signal, the overall
intelligibility of your signal and the audio frequency
response (roughly). No field strength meter can
tell you this information!
Bottom line is, human hearing is
the ultimate destination. It can
be more qualitative that quantity.
However, it is exactly these aspects that make human hearing terrible
for side-by-side comparisons like the one initially described by the
OP.
There are plenty examples of double-blind tests that indicate that
the
participating observer often makes the worst sort of qualitative
judgements.
But any radio broadcaster worth his or her
salt will be able to tell APPROXIMATELY how many
watts a signal is producing (or ERP), especially since
we don't have ionospheric skip in the broadcast
band, all line of sight.
Human judgement is a useful tool, especially when trying to
understand
the hard-to-quantify. However, I find it dubious that anyone has
ears
good enough to hear the quality of an audio signal that is the result
of
+- 1dB of RF gain presented to the front-end.
-1 dB at 100 watts is about 79 watts, so
yeah, most people with a good receiver aren't
going to hear the difference. But some
people very familiar with the signal might
notice the difference.
-2 dB at 100 watts is about 63 watts, which
most people should notice, especially on the
fringe of the service area.
-3 dB is 100 versus 50 watts, and no
**** there's an audible difference!
(This is not to say I
think that the OP only used this method to get his/her results.
Clearly, the OP used some sort of methodology to obtain the +1dB gain
claim. I only suggest that we should be critical of qualitative
results that back up the results we want.)
+1 dB was what our theoretical
difference was, but it may have been more.
Sorry, but we don't have a huge VHF anechoic
chamber, and the proper signal strength meter
to do this properly!
A better qualitative test would be to simply live with the antenna
for a
few weeks, and see what DX one could pull in. Again, totally
unscientific; but this is what average radiopersons (like me, I'm
afraid!) have been doing for decades now.
Like i said, I would love to have a
big VHF anechoic chamber, and place each antenna
on a rotor, and measure every 2 degrees or so,
with the proper uV/meter equipment, but
we don't have the $$ for that. Most people
don't, i don't know anyone who does.
It may be unscientific, but in a certain
way NOT, because you can get field reports from
many people, who all have different receivers,
and different antennas on their cars, etc... so
the results are more of an averaged response.
Bottom line is, is the signal more
intelligible and listenable?
Slick
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