Hi folks - earlier George wrote the two paragraphs below. When using my
K2 or 756 PRO I rarely if ever have the RF gain anywhere but on "full".
When I had my Omni I used it quite a bit. Anyway, when I got home from
work today I unhooked the antenna from each rig and listened to them
with the RF on full and then in turn hooked up the antenna (same antenna
on each rig). As George points out, reconnecting the antenna increases
the noise level. What I found interesting was that for practical
operating purposes the "noise" sounded very similar from each rig.
Unless you are diliberately focusing on differences, you would not give
the difference a second thought. It's perhaps appropriate to say that I
use a horizontal loop (about 260 feet of it) which is a fairly quiet
antenna. It is really too bad that I did not still have the OMNI to
compare it the other two. Since I am a true Elecraft nut it is a bit
tuff for me to admit that I think the PRO is a darn good rig with no
excessive noise that my ears can detect. I certainly don't have 1/100th
the knowledge that many of you have, but I can share my real world
experiences - and I thought this was interesting. The K2's "noise" might
be a little "softer" for lack of a better word. Neither rig creates what
I would subjectively describe as a roar. To me, the big differenc at the
operating level between these two types of rigs is the sound of the cw.
For lack of a better word, it is a bit more "percussive" on the PRO -
but to me that means nothing. Just thought you might find this
"layman's" experience interesting. 73/Tim NX7C
George wrote:
However, and this is the other side of the coin, if one can hear a
certain
noise level with the antenna disconnected, then connecting the antenna
must
increase the noise level. If it does not, then the receiver has a
problem
with excessive internal noise AND/OR there is insufficient gain to bring
the antenna noise up to a level that exceeds the internal noise level.
In
either case, the receiver performance is deficient.
These are all qualitative and anecdotal terms. One man's "quiet" radio
is
another man's radio that does not hear weak signals. Some people have a
great natural resistance to listening to noise, and they usually
implement
this by reducing the r-f gain - which is actually the gain of the
various
i-f sections - until most of the band and internal noise is gone. They
are
willing to trade the ability to pick up the really weak signals for the
comfort of listening to the stronger ones.
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