Today's rigs give the "operator" more control over their signal than at
any time in history. IOW they give the opperator almost limitless ways
to turn a great sounding signal into something brown and smelly. Most
of us do not have the equipment to take advantage of a fraction of these
abilities properly. This leaves the "big rigs" a mass of buttons and
knobs, while the smaller ones end up with menus 3 layers deep with
results depending on which way you go through those menus. We now have
rigs that require you have the "well studied" manual at hand, to get on
the air.
It's only recently that solid state finals have even "approached" the
signal quality produced by a pair of old 6146As in a 32S3 or KWM-2, yes
all this ability has reduced that gain into a loss at the hands of many
hams.
Receivers have reached the area where dynamic range, bandwidth, and
sensitivity are well past the limits of useful practicality and are
bragging rights only. What do we gain with a receiver sensitivity
that's a full order of magnitude (or two) greater than the band noise?
What do we gain by having steep sided 2.8 KHz selectivity where off
frequency signals are over 100 db down when those signals 5 KHz to the
side have 20 over signals "IN" your pass band due to IM products only 30
db down?
Evey once in a while I run into someone complaining about their new rig
not handling the QRM from the side and unable to understand that it's
the transmitted signals fault and not their receiver's. The problem is
that if all new rigs had IM products at least 60 db down, it'd be
decades before much difference would be noticed because of the sheer
number of rigs "out there" that put out poor quality signals. Still,
that's where the change is needed.
Antennas have made incremental gains with the only major change being
antennas that can tune themselves across a range of frequencies. Still,
these are subject to mechanical failure as well as lightening induced
failures and ALL antennas are a number of compromises.
Multi-element antennas produce gain by radiating a signal from one
element and inducing a current in a "parasitic" element that is either
in phase or out of phase with the driven element. The length and
spacing of the parasitic element to the driven element determines
whether the parasitic element is a reflector, or director. You can also
have multiple driven elements.
Methods of driving and loading elements have been developed, but a
parasitic array is a parasitic array with efficiency depending pretty
much on the matching network and the relative size of the antenna, so
very little has actually happened in antenna design. Some cover more
band width than others, some have a more elegant matching system, and
some tune themselves. Some hams use multi antenna arrays and stacks
with diversity reception so they use the best antenna at the time for
the desired contact. Other than that, what's really changed?
73
Roger (K8RI)
On 12/18/2014 12:03 PM, Tom Osborne wrote:
I finally broke down a year or so ago and bought a brand new radio.
That radio sucks with all the menus, etc, and wish I would have spent
the same money on a good, used one. Next time I won't make the same
mistake.
I am definitely a cheapskate :-) 73
Tom W7WHY
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