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Fw: [CQ-Contest] re:Clicks-REAL numbers.

Subject: Fw: [CQ-Contest] re:Clicks-REAL numbers.
From: W8JI@contesting.com (Tom Rauch)
Date: Tue Mar 13 08:54:12 2001
First this:
DJ6RX reports an additional diode to block negative voltage from
the transistor was needed in his, but mine seems to not require
that. I'm sure either he or I will post something when we figure out
what causes that difference between his and mine.

Hi George,

I'm looking at this more as time permits.

 > Whoops, looks like I forgot to send this.  It got put in the wrong
 > box.  The 141T is quite able to see not only the envelope of the
 > keying sidebands, but the actual sidebands themselves.  I've repeated
 > some of these measurements at 10 Hz bandwidth as well as 100 Hz and
 > the sidebands are quite clear.

Even if we clearly "see" the sidebands, it does not mean the level
information is correct. The scope can sample level from more than
one sideband while passing the frequency (and trace position) of
one sideband and add or subtract from the display height.

I am still unclear why the radios were all so close, unless that was
the luck of the draw.

My FT1000(D) is very plainly not "even" in click dispersion, it has
two very evident strong peaks in clicks at about 1300 Hz up and
1200 Hz down from the main signal...with the upper click maxima
much stronger than the lower. The peaks roughly correspond with
where the poles in the transmitter filter are, and this makes sense
to me.

This is entirely do to filter artifacts, because I see it looking at the
IF after the filter. The problem goes away with the slowing of
waveform to the diode switch feeding the filter. Although a different
attenuation scheme might be better, this quick and dirty fix works
for me.

I spent some time reviewing my books, and talking to others. While
I agree with your bandwidth analysis for a single pole filter, there is
no reason to believe the shape of a single pole filter will set
bandwidth ranges. Nothing guarantees a system will have the
response of a single pole lowpass (R/C circuit), even without filter
problems or other artifacts in the output.

As I keep looking at this, it looks like we could contain all the
sidebands within 150Hz or so of the main signal with proper
system design. One solution for maximum speed in minimum
bandwidth would be a Bessel-type filter. This is beyond the normal
use of this reflector, since people care more about results than
theory. Until I have a working circuit, or measure a group of radios,
I'll save further comments.

I did want to make the point we can do a lot better than -50 dB at 1
kHz, much better. My FT1000 gets into test system noise at 1 kHz
now, where it was about -40 dB before at 1.3 kHz

I'm hoping that change reduces complaints about my signal.

I think the main goal is fixing the clicks, not debating something we
already know exists. We already know radios are greatly different,
as least so far as they affect our receiving up or down a few
hundred Hz to a few kHz or two.

I want to fix the clicks, not accept them. It's too crowded to accept
needless clicks.
73, Tom W8JI

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>From Igor Sokolov" <ua9cdc@dialup.mplik.ru  Tue Mar 13 22:58:33 2001
From: Igor Sokolov" <ua9cdc@dialup.mplik.ru (Igor Sokolov)
Subject: [CQ-Contest] Russian DX contest
References: <002b01c0ab85$8cd763e0$dfbdddd0@oemcomputer>
Message-ID: <00be01c0ac12$6e178d80$b8bfd1c3@dialup.mplik.ru>

Just to remind you that Russian DX contest is on this weekend
Russian DX Contest is one of the fast-growing contests. It can boast 5000
participants and more then 3000 QSO/24 hours for the leader last year.
The contest is a good opportunity to work rare Russian oblasts and there is
a long list of trophies and awards for different cathegories.
The complete set of rules, last year results and free software can be found


TR log ver. 6.57 (the latest) is perfect for this contest and scores
everything correctly.
Earlier versions can also be used with some additions to logcfg.dat file.
You can download these additions for the earlier versions of TRlog here:


Or you can use earlier versions of TRlog as it is because contest sponsors
do not require correct scoring of the log in case of electronic submission,
they will do it for you. Very informative UBN files will be available.
The address for email submissions is:


There is also Club competition in this contest so do not forget to  mention
your club.

Hope to meet you in Russian DX contest this coming weekend.

Igor, UA9CDC


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