But then the transmitting antennas in the states might have been curtain
arrays of dipoles with a mere 20 dB gain fed by 250 or 500 KW RF.
73, Jerry, K0CQ
On 12/7/2010 5:08 PM, James Duffer wrote:
Sounds good, especially the rhombic. I visited the VOA (Voice of America)
receive plant at Furstenfeldbruck (spelling?) Germany in the 60s. They used
curtain rhomibics (3 tiers) in a triple space diversity configuration with
diversity receivers RCA and Racal the audio sounded like it was coming from a
record. Then then retransmitted it beaming it to other countries in
Europe/Africa
Jim (wd4air)
Date: Tue, 7 Dec 2010 09:30:05 -0800
From: n4ydu@yahoo.com
To: tentec@contesting.com
Subject: Re: [TenTec] Rhombics
The beverage is inefficient on both transmit and receive. However, you can make
up for the inefficiency on receive with a preamp or matching network to take
advantage of the directivity qualities (providing it is terminated or even
bidirectional) of a beverage. This is not the case for transmitting.
A rhombic would be a super antenna in terms of transmit and receive, especially
if it was terminated and worked in just one direction. One could theoretically
null out noise on the low bands. While some low band yagis exist, obviously the
size and money involved isn't practical for the average ham. This is when a low
cost beverage comes into play and can greatly enhance one's ability to receive.
I use a short beverage on 160 and 80 (sometimes 40) as well as two pennant RX
antennas we good results. It comes in handy during contests to null out strong
signals the the NW and S that interfere with European signals. It cuts down on
the fatigue factor as well.
Beverages are used with success on the high bands at a handful of the
multi-multi mega stations with success as well. I believe they are used as
alternatives to cut down on potential interference from other transmitters
within the station (especially in the case of two stations on the same band
that are interlocked).
73,
Nate/N4YDU
--- On Sun, 12/5/10, JOSEPH DAVIS<iloveantennas@dishmail.net> wrote:
From: JOSEPH DAVIS<iloveantennas@dishmail.net>
Subject: Re: [TenTec] Rhombics
To: "Discussion of Ten-Tec Equipment"<tentec@contesting.com>
Date: Sunday, December 5, 2010, 6:09 PM
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