Barry,
A well designed vertical can be an excellent antenna for longer distance night
time QSOs or close-in daytime ground wave QSOs on 80 and 160 meters; but its
hard to beat a low, horizontally polarized, full sized antenna for the
closer-in night-time QSOs via the ionosphere. Even if its only 25 feet high, a
horizontally polarized antenna will work fairly well on 160 meters and very
well on 80 meters compared to an optimum horizontally polarized antenna about
1/4 wavelength high.
Since your horizontal antenna is very low, a 43 foot vertical might improve
your night time 80 meter coverage at 400-1000 miles out. On 160 meters, the 43
foot vertical is likely to be a disappointment because its efficiency will be
poor, the voltage at the base will be very high (particularly with AM
modulation) and the close-in performance will be only fair.
Perhaps a more productive approach is to improve your horizontal antennas and
matching to make them more convenient to use.
73
Frank
W3LPL
---- Original message ----
>Date: Mon, 16 Feb 2009 19:54:27 -0700
>From: "Barrie Smith" <barrie@centric.net>
>Subject: [TowerTalk] 43' verticals
>To: <towertalk@contesting.com>
>
>I'm seeking advice regarding the 43' verticals I see advertised, both from MFJ
>and DX egineering.
>
>While regional babbling on 75 and 160M is not my primary purpose year-round, I
>do like to chat with friends during the winter, mostly on (gasp) AM.
>
>My antenna now is a very low 400' doublet, fed with open-wire line. It works
>well for regional contacts.
>
>The problem is that I'm using a home-brew, great, giant, truely-balanced,
>link-coupled tuner to "match" the 50 ohm output of my transmitter (a
>transmitter, not a linear) to the 600 ohm line.
>
>While this tuner works great, QSYing is an enormous PITA. It takes three to
>five minutes to retune everything when I move more than a few KC.
>
>My thought is that if I had the 43' vertical, I could run the coax out of the
>transmitter, skipping the tuner, and when I wanted to QSY, I'd simply redip
>the final and be on my way. Link-coupled finals match just about anything.
>
>So, how well would this 43' vertical work on the 200 to 1000 mile range?
>
>The price of the MFJ vertical is much less than the DX Engineering. Is the
>added cost of the DXE worth it?
>
>Any help appreciated.
>
>73,
>
>Barrie, W7ALW, DN36au,
>QRV 6M, 432 & 1296 EME
>_______________________________________________
>
>
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|