I have purchased a large farm property (1500 Hektares) in a remote area in the western fjords of Iceland called “Otradalur”.
The QTH is 65 degrees 39 minutes 49.2 seconds North, 23 degrees 33 minutes, 58.8 West (in decimal 65.66367N, -23.56633W)
The Locator is HP85FP
I have built three Rhombic antennas in the directions of JA, EU and the US.
The EU and JA Rhombics are 210 feet on each leg and about 50 feet high. The USA Rhombic is 350 feet on each leg, has a tilt angle of 70 degrees and is 80 feet high. The feedline to the USA Rhombic is more than 3000 feet long and presently carries 5 x 600 ohm open wire transmission lines (30,000 feet of wire).
from QST, September 1942:
Book review of “Rhombic Antenna Design” by A. E. Harper.
“…Obviously useful for engineers engaged in the design of communications circuits, this book also should be valuable to the amateur with engineering background in that happy day when rhombics again can get to work pushing ham signals to the far corners of the earth”
That happy day has now arrived.
All three Rhombics are of a three wire design, this broadens the pattern, smooths out the impedance and according to Harper, this reduces precipitation static by 9 dB.
I use #10 CopperWeld for my EU and JA Rhombics and #8 Hard Drawn Copper wire for the USA Rhombic.
Although I had used Rhombics before, while serving with the UN and at TFA Coast Station, I was unprepared for the amazing performance of the antennas. There is a wonderful “3-dimensional” effect on received signals, the antennas are extremely quiet and my location has zero man made noise. The large capture area of the Rhombics probably account for the way they sound. Signals arrive in and out of phase simultaneously at different parts of the antenna.
Siggi, TF3CW described my farm as Ham Radio Heaven.
What a pleasure!
I estimate the total amount of wire in my antenna system to be around 60,000 feet – this includes the feedlines.
I feed the Rhombics with 600 ohm open wire feeders, with 1/2″ Heliax going underground to the shack through 12:1 Balun transformers.
I terminate the Rhombics with a long open wire feeder made of stainless steel wire shorted at the end – this makes it possible to ground the antennas at the far end for static dissipation. Furthermore, the Balun transformers are grounded at the near end as well.
I feed the three Rhombics into a power combiner (WX0B StackMatch) this enables me to switch instantly between antennas and also transmit and receive on any combination of the three antennas simultaneously.
I use a Yaesu FT1000MP Mark V into an Emtron DX-3 Linear Amplifier at 1KW and a Yaesu FT1000MP Mark V Field into an Emtron DX-2SP Linear Amplifier at 1KW.
I have purchased 2,200lbs of #9 AlumoWeld wire for my future antenna projects.
Some of the ideas floating around involve the use of the mountains as 400 meter high supports and stringing 1 kilometer long wires across the valley at 200 meters height.
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