Hi Cal,
you have almost perfect ground situation with your radial field, take advantage
of it by using RX vertical arrays, either some flags, arrays of them for
particular direction, or switchable circle vertical arrays.
You need to detune the tower on receive if RX arrays are close over radials.
Beverages don't like good ground, but Misek's SWA (?) antennas might work.
You can improve your TX antenna by hanging parasitic directors and reflectors
(dipoles or loops) of the big tower.
Sounds exciting, GL and HNY!
Yuri, K3BU.us
www.MVmanor.com
----- Original Message -----
From: Cal Zethmayr
Date: Friday, January 6, 2012 11:52 pm
Subject: Topband: looking for suggestions for rcv antenna for this years CQWW
160SSB
To: topband@contesting.com
> First, thanks to Mike W0BTU for directing me to this forum.
> Last year was just my second attempt to work the CQWW and I
> guess I did fairly good for a newbie...Single Op Low Power, 1st
> in Florida, 2nd in Call area 4, 7th in US and 11th in North America.
>
> BUT only worked a handful of DX out of Europe. The few I did
> work asked me why I wasn't answering all the stations they could
> hear calling me. The vertical tower I used the last two years
> gets out great, but doesn't hear as well.
>
> I only operate from sunset to sunrise in this contest because I
> am using the 466 ft tower at the radio station where I work.
> Daytime there the tower is hot with about 10 amps of RF from our
> 3.1kw AM daytimer. There is 100kw FM out of a 10bay ERI dual
> polarized stack at the top of the tower. I do suspect the FM
> causes some suppression of signals on my rcvr because when the
> FM signs off at midnight, I do get better contact numbers per hour.
>
> I get great signal reports from almost everyone I've worked on
> this BIG STICK. I just pull the knife blade from the AM ATU and
> connect with a coax balun directly to the station ground system
> and the copper strap to the tower. It's 36' wide on each side.
> LOTS OF STEEL up there. loads up great with very low swr.
> Especially up near 1.9
>
> This year I just got a chain link fence finished around the
> entire 5 acres. SO I considered putting up a loop for receive.
> It would be a total of 2050 feet. Would take about 300 feet of
> coax to center feed it at the back of the property. I calculated
> the cost of building around 100 2x2 A Frames to get the loop up
> about 30 feet, and would tie wrap the A frames to the fence
> posts... the lumber and hardware alone would be over a grand!
> and that does not include the cost of coax and the 2050 feet of wire!
>
> I've read a lot of the articles on the Beverage including the
> ones from the 20's... and after reading Mike's info and at his
> suggestion I looked up the archives on Beverages here on the
> forum. Looks like running a Beverage across the 250 ft wide
> ground system for the AM would not be a good idea?
>
> Course I would have an excellent ground source at the SW end of
> the Beverage and could easily have a full wave aimed NE at
> Europe.
>
> Another thought would be to hang a fullwave extended Zep(fed
> with ladder line) from the station tower. I can climb the
> tower and hang a pulley at any height I want. Then I could pull
> the Zep up late in the afternoon. I might even be able to leave
> it up after trying it out a weekend before. The lower end
> would go to a 40 ft push up mast at the NE corner of the chain
> link fence.
>
> One of my ham club friends plotted the loop with EZNEC...and is
> going to run plots of 4 different configurations of the
> Zep..(based on different positions up the tower from 100' to 250'.
>
> SO SUGGESTIONS ANYONE?
>
> Thanks
>
> Cal Zethmayr
> W4GMH
> Crestview, FL.
> W4GMH at cox.net if you want to contact me off the list. I can
> send you some google earth pix of the layout.
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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