Igor, are you saying that you could not view the numbers at his website? If 
anyone has difficulty getting to the numbers, let me know and I can repeat them 
here, but for now I will just refer you to the website again.
Here is a short url for that page:
Scroll down to the first handwritten table. The left-hand column lists the 
different radios tested. 3 columns to the right shows test results for 
different pulse frequencies. Presumably, a higher pulse frequency means the 
interference spectrum is more spread out around the wanted signal. However, 
this is not quantified or described in detail. Remember, results of this test 
method are strongly dependent on the design of the pulse generator etc, so the 
if someone would like to duplicate or compare to his numbers, they would have 
to duplicate his exact equipment, or come up with a new similar test setup that 
could be regarded as a standard. For each radio, there are two rows of results 
(for each pulse frequency). The first row represents the radio without 
preselector (but modified to add a roofing filter, except in the case of the 
IC-7300). The second row represents the same radio with the addition of the 
preselector, which is his personal design, also described at the website. 
 If I am not mistaken, the preselector is entirely passive. All the result 
numbers are negative dBm values. This means that a smaller negative number 
represents a stronger interference signal that is in some sense tolerated. E.g. 
-20dBm is a great result, but -50dBm is a poor result. None of the numeric 
results can be translated into, or compared with, numbers published by Sherwood 
or the ARRL. However, he makes a pretty good case that his measurement method 
might be "better" than those conventional measurements in representing the 
performance characteristics that are relevant in practical ham use under heavy 
interference from close-in strong signals. For the ARRL or Sherwood to adopt 
his approach they would likely have to invest in additional test equipment 
including custom-built items, and justify a standard method of doing this kind 
of testing, so I am not holding my breath. The inclusion of the IC-7300 shows 
that the website content is not very old, but other than the K3 
 he has not included any of the several radios on the market today that 
incorporate roofing filters as a standard part of the design. Perhaps we could 
hope that some kind hams in Europe would lend him additional radios for testing 
with his unique test equipment. As to his own conclusions, they should be 
covered by the text I already translated. Are any of his statements (as 
translated) unclear? Remember, no real world radio has a "true" performance 
level even in principle. Every time we look at performance numbers, they 
reflect imperfect concepts developed in our small human minds, whether they are 
considered "standard" or not. A concept such as "better" is usually not an 
objective way of describing things.

Erik K7TV

-----Original Message-----
From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On 
Behalf Of Igor Sokolov
Sent: Saturday, April 07, 2018 6:49 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] OE3HKL's Measurements


Can you possible give a summary of the results of his measurements and 
conclusions he has made?

73, Igor UA9CDC

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