[TenTec] Jupiter Bashing/eHam Reviews

[n4lq@iglou.com]

I want to see them test rigs for cw recption by using an artifical QRN 
generator and a code copying program. They could do this at different 
bandwidths. Then do the same test with a panel of cw operators who simply 
listen to the cw through this QRN and give a subjective rating of 1-10. I 
think the results might be surprising. 

Steve N4LQ

-----Original Message-----
From: "Tom Rauch" <w8ji@contesting.com>
To: wa3fiy@radioadv.com, tentec@contesting.com, Duane Grotophorst 
<n9dg@yahoo.com>
Date: Wed, 1 May 2002 09:10:40 -0400
Subject: Re: [TenTec] Jupiter Bashing/eHam Reviews

> > True indeed, so far most of the measured testing done
> > at the ARRL and their peers is focused on the RF
> > signal handling traits of a radio, little or no
> > testing is done with overall RX system distortion of
> > complex (voice type) audio signals. Nor is there any
> > meaningful measurements done to determine the overall
> > contributed noise of the RX's RF/IF and AF stages. The
> > tests they do are very valuable, but they only tell
> > half the story of how a particular RX really performs.
> > That unfortunately leaves some very measurable
> > parameters up to subjective interpretation.
> 
> It's unfortunate that we have decided the lack of useful data somehow 
> means all data is useless, and that many have concluded measurements 
> are meaningless. 
> 
> Part of this is because some parameters are not measured, another 
> part is because we often don't understand what the measurements 
> actually mean.
> 
> All of this can be corrected. The ARRL is *very* responsive to 
> reasonable suggestions for testing, as proven by changes they have 
> recently made in response to input from reflectors like this one.
> 
> For example...in the past the ARRL published only 20kHz and wider 
> blocking and IM3 tests for receivers. Those measurements are useless 
> for close-spaced performance of a receiver because they are outside 
> the bandwidth of most roofing filters, and the wide spacing test 
> hides IM and blocking problems that appear after the roofing filter.
> 
> After some conversations on the Topband reflector, the ARRL changed 
> to include 2kHz spacing tests. The closer spaced testing sorts out 
> second mixer and later stage problems in receivers, and makes a 
> surprising change in the pecking order of rigs.
> 
> As I understand, they are now going to include CW transmitter 
> bandwidth measurements.That's something else that was long overdue, 
> as anyone who works CW on crowded bands probably has noticed.
> 
> If anyone has any suggestion, maybe we can hash it all out and make a 
> reasonable suggestion to the ARRL to include a few more tests.
> 
> Perhaps an audio response test and detector IM test would also be 
> useful to those who are more "sound oriented" in preferences.
> 
> Perhaps someone would be willing to write an article describing how 
> to tie measurements into real-world operation. That would be 
> extremely useful to correcting the myth that measurements are 
> meaningless.
> 
> 
> 
> 73, Tom W8JI
> W8JI@contesting.com 
> 
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