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From: V.LONG.SA@OCF.compuserve.com (V.LONG.SA@OCF.compuserve.com)
Date: Wed Jul 3 12:32:10 1996
To: >INTERNET:cq-contest@tgv.com at OCF_INFORM
cc: >INTERNET:fritz@erinet.com at OCF_INFORM
*cc: V.LONG.SA
*cc: Howard Waggoner at WTMSM1
    Licking County Contest Group
    2A OH  (100 watts)
    Operating from Hebron, Oh
    Callsign: WD8E

    507 SSB (x 1)  (+ 53 on 6m, 12 on 2m & 2 on SAT)   =   574 pts
    737 CW  (x 2)  (+ 5 packet & 1 on 6m)              = 1,486 pts

    574 + 1,486                                        = 2,060 pts

    POWER LEVEL MULTIPLIER  (2,060) x 2                = 4,120 pts
    BONUS POINTS                                       =   700 pts
    GRAND TOTAL                                        = 4,820 pts

    Last year's score was 2,956 points.

           160   80   40   20   15   10   6   2   SAT   PACKET
    SSB     0   161  175  118   44    9  53  12    2
    CW      0   136  430  130   41    0   1   0    0      5


     SSB: Yaesu FT-990  into Mosley 33jr and G5RV
     CW:  Yaesu FT-890  into Mosley CL33 and G5RV
     VHF: ICOM 706 (6/2m) into Hy-Gain 66DX at 30 ft and Cushcraft 11 ele
     SAT: Yaesu FT-736
     PACKET: Kenwood TS-711A and PK-232 (lastest model)
     GENERATOR: Coleman 7000 watt (it ran 24 hours non-stop)

     COMPUTERS: (2) Compaq 486 50 & 75 mhz color laptops (8mb ram)
                (1) Compaq Pentium 120 mhz   "      "    (48mb ram)

     SOFTWARE : CT version 9.00  (Flawless!)

    Note to all: No bonus points this year for ARRL members operating.

>From aa4lr@radio.org (Bill Coleman AA4LR)  Wed Jul  3 17:38:20 1996
From: aa4lr@radio.org (Bill Coleman AA4LR) (Bill Coleman AA4LR)
Subject: cw forever?
Message-ID: <v01540b01ae003fb3356a@[]>

>I would like to hear from contesters with digital mode and cw experience
>regarding their thoughts on how cw, rtty, and state of the art digital
>modes compare for contest-style weak signal work.

Theoretically, CW doesn't stand a chance.

Bob McGwier N4HY did a test a number of years ago (10?) with another friend
whose call I can't remember. They were doing "ionospheric sounding" at 144
MHz, sending a string of dots, and then reducing the power level.

Their receiving apparatus consisted of a PC with a DSP card (woefully
underpowered by today's standards) running FFT's and graphically displaying
the results on the screen. Sort of a poor man's spectrum analyzer for audio

He discovered that he could visually detect signals on the spectrum
analyzer that HE COULDN'T EVEN HEAR. He even had visual CW QSO with this
apparatus, and theorised that an OSCAR-class station could easily work
moonbounce this way.

On that basis, if you are talking about direct CW detection by ear, it
doesn't stand a chance against modern DSP techniques. But, even using DSP
CW detection, there's reason to doubt.

When you look at the theory, in the presence of gaussian noise, FSK has a 4
dB advantage over OOK (on-off keying - ie CW). Now, the noise on the bands
isn't gaussian, and there are other things to consider. The overall
bandwidth, which is primarily defined by the data rate (plus the modulation
index for FSK), is probably the biggest factor. For the same data rate, FSK
takes more bandwidth, which in turn allows more noise. Using a small
modulation index, you can get FSK down to less than twice the bandwidth,
which still maintains a noise advantage.

DSP is a lot cheaper today. Many personal computers have more than
sufficient processing power to do sophisticated DSP without special

Even so, CW by ear is still fun....

Bill Coleman, AA4LR, AA96LR      Mail: aa4lr@radio.org
Quote: "Not in a thousand years will man ever fly!"
            -- Wilbur Wright, 1901

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