October issue of CQ has a construction article for a quarter-wave
sloper on 160 meters. I was curious as to what antenna modeling
would predict for resonance if the average contester were to
install one on his tower. The fellow that built this of course was
lucky or smart. The model shows a 160 meter quarter wave sloper
(with a little pruning) attached to a 50 foot tower and a 3 ele
yagi resonates easily inside the band. With the antenna resistance
around 23 ohms and some ground loss a good match to 50 ohm cable
can be made.
If it were installed on a 70 foot tower the sloper length would
drop to 86 feet and the antenna would be 150 ohms at resonance.
Removing or adding yagi's changes things even more. Trying to find
the right length of the sloper wire empirically on different
tower/antenna combinations might not be a good idea on the morning
of the World Wide. I'm not sure when the better idea would be to
shunt feed the tower or switch to the inverted L.
Many years ago I had a 70 foot tower with a tribander. I installed
a quarter wave sloper for 75 meters (about 70 feet long) at the top
and it worked very well often out preforming a delta on a 90 foot
tower about 100 feet away. I noticed it was somewhat directive so
I added another and that was the end of slopers for me.
Rich KL7RA
>From cns-sd@ix.netcom.com (Art Wallace) Sat Sep 28 00:36:16 1996
From: cns-sd@ix.netcom.com (Art Wallace) (Art Wallace)
Subject: Fwd: New Kenwood Radio Announced
Message-ID: <199609272336.QAA13148@dfw-ix1.ix.netcom.com>
---- Begin Forwarded Message
Good news gang! Kenwood has announced a new radio today- the Kenwood =
TS-570D. From the ad slicks it really looks like a FB rig. This radio =
was obviously designed with the new distribution and sales channels in
=
mind. Sharing the front panel with a very nice weighted optically =
encoded VFO knob is a 40 position detented switch assembly enabling =
quick QSY's from HF to CB.
Although it would give the appearance of dual VFO and receiver mixed =
audio, alas it comes with neither. However, included at no additional =
charge is a ROGER "BEEP" button and some new enticing features only =
found in this radios DSP circuitry. Along with standard features of =
bandwidth and noise cancelling come a new digital ECHO and digitally =
mastered waterfall background sounds for taking over that bothersome =
QRM'ed channel.The waterfall emulator has its own PTT control so as not
=
to wear out your fingers.Yes gang. this radio has enabled XMIT on 10mhz
=
for those wishing a higher profile in their radio life.These radios =
should be in your dealers soon so call now!
................................................
Hmmmmmm. Sounds like a "Fine Business" radio.
All I wanna know is if it will work with my Gold Plated D-104 Eagle.
If so, I'll take one!
Art KK6 "X-Ray November" Mobile in Imperial County for Cal Qso!!!
................................................
>From w7zrc@micron.net (Rod Greene) Sat Sep 28 01:07:00 1996
From: w7zrc@micron.net (Rod Greene) (Rod Greene)
Subject: 160 sloper
Message-ID: <2.2.16.19960927174309.256f50d6@micron.net>
Rich,
I have a friend who has the same situation you mention. He has a 70'
Rohn 25 tower with a TH6DXX and HyGain 2 ele 40. A sloper for 80 tunes
well but making a 160 sloper work has not been a successful venture yet.
I was wondering if an additional "tuning stub" wire clamped at the top
of the tower would help to restore the resonance on 160.
Any thoughts or suggestions would be appreciated.
73, Rod
At 10:52 PM 9/27/96 utc, Gilmore Creek Geophysical Observatory wrote:
>October issue of CQ has a construction article for a quarter-wave
>sloper on 160 meters. I was curious as to what antenna modeling
>would predict for resonance if the average contester were to
>install one on his tower. The fellow that built this of course was
>lucky or smart. The model shows a 160 meter quarter wave sloper
>(with a little pruning) attached to a 50 foot tower and a 3 ele
>yagi resonates easily inside the band. With the antenna resistance
>around 23 ohms and some ground loss a good match to 50 ohm cable
>can be made.
>
>If it were installed on a 70 foot tower the sloper length would
>drop to 86 feet and the antenna would be 150 ohms at resonance.
>Removing or adding yagi's changes things even more. Trying to find
>the right length of the sloper wire empirically on different
>tower/antenna combinations might not be a good idea on the morning
>of the World Wide. I'm not sure when the better idea would be to
>shunt feed the tower or switch to the inverted L.
>
>Many years ago I had a 70 foot tower with a tribander. I installed
>a quarter wave sloper for 75 meters (about 70 feet long) at the top
>and it worked very well often out preforming a delta on a 90 foot
>tower about 100 feet away. I noticed it was somewhat directive so
>I added another and that was the end of slopers for me.
>
>Rich KL7RA
>
>
----- Rod Greene, w7zrc@micron.net, <>< -----
>From jwthompson@key-net.net (John W. Thompson) Sat Sep 28 02:01:43 1996
From: jwthompson@key-net.net (John W. Thompson) (John W. Thompson)
Subject: SOAB
Message-ID: <19960928010142328.AAA195@LOCALNAME>
One thing these guys forgot to mention:
Those contesters who contest to STOP hallucinating...
Yes, the voices stop about 11PM EST Sat. nite....
Wasn't that idea of fusing with your radio STOLEN from Koontz's "Midnight?"
73, JT K3MD jwthompson@dubois.key-net.net
>From donovanf@sgate.com (Frank Donovan) Sat Sep 28 02:01:09 1996
From: donovanf@sgate.com (Frank Donovan) (Frank Donovan)
Subject: Multiple-Choice Packet-in-Contests Quiz (fwd)
Message-ID: <Pine.OSF.3.95.960927205701.29647A-100000@jekyll.sgate.com>
Rick,
I have a HUGE problem with your recommendation! If an operator
misrepresents the class he was competing in, what else in his log might
also be misrepresented??
If an operator is using packet spots, and enters as SO, the only
legitimate disposition of the entry is disqualification.
73!
Frank
W3LPL
donovanf@sgate.com
---------- Forwarded message ----------
>From: "Rick Craig, N6ND" <n6nd@n6nd.wanet.com>
>To: cq-contest@tgv.com
>Subject: Re: Multiple-Choice Packet-in-Contests Quiz
>If you can make a good case that a single op station is using
>packet spots to find multipliers, then his log should be reclassified to
>SOA. What's the problem with that?? If the committee (or judges)
>doesn't have the balls to enforce the contest rules, then we are all
>beating a dead horse.
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