[1000mp] 1000-Field Review ... Notice what's MISSING?

[Hare,Ed, W1RFI]

-----Original Message-----
From: Billy Cox

> > >The ARRL had stated they were moving from the 20 kHz to the
> > >more useful (and accurate) 5 kHz spacing measurements ...
 
> > The numbers are there.

> The original copy (yesterday) had NO 5 kHZ measurements ...

Absolutely correct. Fortunately, someone noticed and called me on the phone
this AM, almost as soon as I got in.  I figure out it was an oops and
immediately put that caller in touch with Brennan Price, the new Product
Review editor. (Talk about a baptism in fire!)  After quite a bit of back
and forth, the Editor decided that this one should be corrected at the
printer rather than with a Feedback.  It cost a bit of staff time and a few
hundred dollars for the new printing plate, but it seemed the right thing to
do.

> Somewhere that needs to change also, as on one hand prior 
> tests were @ 20 kHz, the newer standards are going to be @ 5 kHz. 

Actually, the old test standards were that we reported 20-kHz and 100-kHz
test results in the test table and, for most receivers, did a set of swept
tests from +- 2 kHz to 100 kHz from the nominal test frequenices on 20 and
80 meters.  The change that was made was to add the test results for 5 kHz
spacing to the test-result table.

The most "historical" DR test data was done at 20 kHz spacing.  Dynamic
range is generally pretty much fixed once one is about 50 kHz away from the
desired frequency, degrading in different ways as one gets closer in,
depending on the internal design of the receiver filtering. If a single
number were to be used, 20 kHz probably represents a reasonable number that
averages the results.  No single spacing can be representative of all the
different ways that receivers respond, so even that 5 kHz spacing number
can't tell the whole story. I expect that 20 kHz will still remain the
number that is discussed in the text, to allow the best possible comparison
with what has gone before.  

Those who want to know more will look at the 5-kHz numbers in the table and
those that REALLY want to know more will download the expanded test result
reports.  I am logged in from home now, so I can't toggle over to the ARRL
Web page to see if the expanded report is ready yet, but if not, expect it
within a week or two.

73,
Ed Hare, W1RFI
ARRL Lab