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CT keying

Subject: CT keying
From: g-taylor4@tamu.edu (g-taylor4@tamu.edu)
Date: Tue Dec 21 13:55:13 1993
> >
> > Are any other CT users interested in this feature?
> >
>
> I think that the speed change and half-space features are long overdue
> in CT.  I cast my vote IN FAVOR!

Yes...used CT for first time in SS this year but found I prefer NA
primarily because I can adjust spacing in exchange, number of requests for
fills noticably up...at least with a qrp signal.

Greg KD4HZ




******************************************************************************
Dr. Gregory S. Taylor               !MAIL:  110 Dairy Science Building
Extension Program Leader for        !       College Station, TX 77843-2124
  Community Development             !VOICE: 409-845-4445
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>From Ed Gilbert <eyg@hpnjlc.njd.hp.com>  Tue Dec 21 20:28:58 1993
From: Ed Gilbert <eyg@hpnjlc.njd.hp.com> (Ed Gilbert)
Subject: W2CXM alumni
Message-ID: <9312212032.AA01021@hp.com>

>After seeing the "On Wisconsin!" msg I was curious - How many W2CXM alumni
>are on here?? I am aware of myself, K1EA, WB2CPU, K3RV (not on reflector).
>Anyone else out there??
>73 - Bill - N8ET
>

EE, class of '71.

Ed Gilbert, WA2SRQ

>From draperbl <draperbl@smtplink.mdl.sandia.gov>  Tue Dec 21 20:16:37 1993
From: draperbl <draperbl@smtplink.mdl.sandia.gov> (draperbl)
Subject: CT default for SS precedence
Message-ID: <9312211416.A07223@smtplink.mdl.sandia.gov.>

As I was preparing my SS logs to mail to HQ, I ran across a 
note I'd made during the contest . . . thought I pass it by
the SSers on the reflector to see what you think.

CT automatically puts an "A" in the precedence field during
Sweepstakes.  While it's nice to have a placeholder in
the very long Sweepstakes exchange field (particularly
one that is correct more than half of the time), I often had
that "Gee, did I forget to turn off the water" feeling -- did 
W2XYZ really say he was running low power, or was I in too 
much of a hurry to change it to a "B"?  Sound familiar?

Wouldn't it be better if CT used something like an "X" as the 
precedence placeholder, not allowing us to log the contact 
until we replaced it with an "A", "B", or "Q"?  For those
contesters who prefer to have the default "A", Ken could make
this a startup switch option ( -x ?).  

Comments?  How does Tree's program handle this?  The last copy
of NA that I used also inserted a default "A".

    Adios y Feliz Navidad,
    
      Bruce  AA5B


>From howie cahn <howi@world.std.com>  Tue Dec 21 21:05:32 1993
From: howie cahn <howi@world.std.com> (howie cahn)
Subject: Evaluating station performance
Message-ID: <Pine.3.87.9312211632.A2759-0100000@world.std.com>


    Since there's no contest category for 'QRP stations with trap dipoles'
to compare my scores against, I'm often not sure how I've done when a
contest ends. To try to get a standard to measure against, I did a little
data analysis exercise to see if I could figure out the relation between
power radiated and contest score. If such a relationship could be
determined, not only would I have a means of evaluating how I did, but
also a mechanism for quantifying the effects of changes to a station:
eliminating .5 dB of coax loss, adding an extra beam element, etc. The
procedure I'll describe wasn't a major effort -- doing the analysis took
about a half hour and it will probably take about as long to write it
up -- so I don't claim great precision in the results, but hopefully the
general conclusions are valid. 

    I started out by noticing that the winners in this year's CQWW cw
(high power, single op) had about 10 times the number of QSOs, 10 'QSO
dBs', as I did, while running about 40 dB more effective radiated
power. The two points establish a line with a slope of 4 power dBs per
QSO dB; i.e., it takes 4 dB more power to get 1 dB more Qs. To see if
this result made sense I tried a few more data points.  I made a graph
with one axis (x) as the effective radiated power (in dB relative to 1
watt into a reference dipole), ERPd.  The other axis (y) is the total
number of QSOs made. Both scales are logarithmic. On this graph I
plotted four points -- representing the winners in each of three
categories: high power, low power, and QRP, and the results for my
station. I assumed the three winners used the maximum power allowed in
their class. I calculated their average antenna gain by taking the
gains of their antennas on each band and weighting them based on what
percentage of the total contacts that band accounted for. For example,
AA2U has stacked 6-element tribanders on the upper bands, a 2-el on 40,
and a loop for 80/160. I estimated that this averages out to 10 dBd
gain. 

    The resulting data points were:
        Call    QSOs    Effective Power
                          (ERPd watts)
        -------------------------------
        K1KI    2927        24000       High power winner
        K2ZJ    1292         2000       Low power    '
        AA2U     734           50       QRP          '
        WB2CPU   234            3       me 

    From these numbers, I'd like to claim victory in CQWW -- based on
Qs per effective power.

    Seriously though...  The points are surprisingly colinear. The only
anomaly was that AA2U, the QRP winner, was a bit over the line that
connects the other three. Since Randy often places in the top ten in
the LOW POWER category while running QRP, this is not unexpected. The
slope of 4, determined earlier, seems about right. I won't try to draw
the graph here using ASCII characters, but you can start with a point
representing 1 watt, 300 Q's and draw the line through it with a slope of
four. 

    The results suggest to me:
        a. Increasing your power by 1 dB would have increased your QSO
total by about 10 ** .025 ==> 6%. A 2 dB increase would give 12% more
Qs, a 4 dB increase 26%, etc. What this means is somewhat subjective.
Those of you near the top of your category would probably sell your
wife to Robert Redford for 6% more QSOs. It certainly might pay to
upgrade some long coax runs to hardline and worry about the various
tenths of dB losses in switches, tuners, relays, etc. For me, though,
there are much more cost-effective ways of improving things. My only
40M dipole radiates east/west. Adding one facing south, a $40
investment in wire and coax, would add an S-unit or two to parts of
the Caribbean and South America. 

        b. It might be surprising that the line was linear over a very
wide power range, about 5 decades; from about 1 watt to tens of
kilowatts. Actually, my experience indicates that it may be valid even
lower than that, say down to .1 watt, or even less, of effective power.

    While you're not going to be competitive with the big guns,
you can make a reasonable number of DX contest QSOs with QRP power and
simple antennas. In this contest the graph suggests that you could have
made over 400 QSOs with five watts and dipoles, and, 300 QSOs with just
one watt and dipoles. Since these numbers were derived mostly by
analyzing the contest winners, they represent the upper bound of what
could be done. But, they're good targets to shoot for.
    
        c. As a sanity check I tried repeating the experiment using
last year's results. Again, the data formed a reasonably straight line
with a similar slope. The line was raised a little (higher y-intercept)
which is to be expected since upper-band conditions were so much better
then. (The best illustration of how much 10 meters has deteriorated in 
a year is the fact that I made more QSOs with 5 watts and a dipole
during the last year's contest on 10 than K1AR/K1EA did there this
year.)
 
    I hope this information helps in evaluating station performance. To
save bandwidth here, I've described things quickly. I'd be glad to
elaborate or discuss other people's thoughts on the subject. 


        73,

        howie, wb2cpu
        howi@world.std.com

        (with everyone giving their academic affiliations today, I'll add:
        Cornell '70 EE
        W2CXM Trustee 1967-70)



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