During Desert Storm One, there was a MARS station in Florida which had a
Rhombic designed for the short path to Kuwait. I believe each leg was
something on the order of 1000 feet providing something like 16 dBi gain at
14 MHz. As phone patch director for the Mid-West, I observed that Florida
based Rhombic just open and close the band on Mars frequencies just below
the 20 meter amateur band.
I have used about 500 feet of wire stapled to the top rail of the split rail
fence on three sides of my acre lot as a low noise receiving antenna. I used
a transmatch and a noise bridge set to 50 ohms to tune the antenna for the
frequency I was operating. Although the signals were much less on that low
wire antenna, the signal to noise ratio was much greater allowing me to work
4X4 stations on 80 meters with some regularity.
73 es DX,
Gary - AB9M
-----Original Message-----
From: Nathan moreschi
Sent: Tuesday, December 07, 2010 11:30 AM
To: Discussion of Ten-Tec Equipment
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
OK on Beverage Eff. Most use Beverage to receive and vertical or
dipole to transmit. I am still thinking why the Beverage is so
ineffecient for transmitt. jjdavis
On Sun, Dec 5, 2010 at 4:14 PM, Richards <jruing@ameritech.net> wrote:
> We used a steerable two Beverage array (receive only) for the 160 M SSB
> contest last Feb, and it was fabulous. I would not want to transmit on
> that. Final results... 5th place in North America and First in Section
> 8. (We had as many contacts as some of the others, but guys on the East
> Coast with multipliers to EU killed us...)
>
> The steerable Beverage array was a wonderful receiving antenna - we
> could null off direction signals, and focus on the immediate contact we
> were taking at the moment - a very helpful tool dealing with the pileups.
>
> We used a tower as a vertical transmitting antenna, which worked great.
>
> I doubt if I will ever have either of those on my suburban lot.
>
>
> ========================== JHR ===============================
>
>
>
> On 12/5/2010 3:30 PM, Ken Brown wrote:
>>
>>> If u have land consider the Beverage antenna. I have two and they are
>>> simple to build and performance is excellent.
>>>
>> Depends what you mean by performance. You can get a good directional
>> pattern with a Beverage, and their efficiency is very low.
>
>
> ================================================================
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>
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