I think the notion of normalizing MDS when measuring
dynamic range is absolutely necessary. It is commonly
what we do in the Orion when we adjust the RF gain.
Further in the case of the Orion you can tune the 3
parameters of the AGC which I think further enhances
MDS in the face of a given dynamic range especially in
varying QRN conditions.
Just because the 9000 has a tunable filter in the
front end and an IPO button as its means of improving
dynamic range, is no reason to then ignore the
alternative means of optimizing MDS v dynamic range in
other designs such as RF gain/AGC tuning. I think
this will become even more evident as SDR becomes more
and more dominent. My old HQ-170 had a preselector
nothing I ever owned before has contuniously adjutable
BW to 100hz and a tunable AGC. It took me a while to
understant how this gives me an advantage.
I think there needs to be a standard developed of
"best performance" that should be determined in order
to compare rigs, that takes into account the means
available by which best performance is obtained. I
routinely operate my Orion at 100hz bandwidth on CW
and fool with the AGC and RF gain + - dsp noise
blanker, diversity reception etc, because it offers me
"best performance". I also run the offset around
350hz. By doing so I can reach into the mud and hear
things I can't otherwise hear. There is no reason to
limit the performance analysis to 500hz bandwidth
because that is how we evaluated the TS-820 30 years
ago. You can make those comparisions if you like, but
they are worthless if by doing so you limit the actual
performance available in the radio.
Its like getting in to test a ferrari and putting a
goveror on the engine so it can't go fast enough to
get out of 1st gear, just so you can compare how the
ferrari compares to the performance of a 30 year old
VW. It is just artificial. The 20khz IMD spacing of
3 decades ago is still dutifully performed. That test
had some usefulness when IMD was 50DB. At 100 + db no
one even considers that a standard worth considering
any more, because the measurement has essntially no
real life sequella. I want to know how the thing runs
at 1 khz spacing, not 20khz. I want to know at what
point the performance falls apart. That number is a
useful number to me if I'm gonna drop 10K on a radio.
This goofy "I raised the power to 200W and made the
contact" or "My audio was so good it got me through
the pileup" is worse than nonsense. It tells you
absolutely nothing except what kind of fantisy land
this author lives in.
These rigs are very complicated and subtle in their
operation. Nothing that K1ZZ tells me in his weekend
of operation is anything but a superficial and almost
trivial understanding, or mis-understanding of how the
system works. He in fact in essence said he wasn't
going to compete because he really didn't know how to
operate the radio. How is this then a rational review
of how the radio operates in a CW contest? There is
no reason a rig is not continually and honestly
reviewed by the power that be at QST, the same as cars
are reviewed over tens of thousands of miles and
months & months of driving with regular updates on how
the thing works in the car magazines.
Someone actually putting their Noogies on the line in
a contest would be a good review, someone pretending
to be in a contest is no review at all. Notice the
comment that nothing could be heard on the 9000 that
couldn't be heard on the cheap rig. Now that's what I
call an honest statement, but what if the reason
nothing weaker could be heard was becuse the joker
running the radio didn't know how to make the radio
access that layer below the crud he was hoping to
access?
We need a better measuring protocol.
73 W9OY
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