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I have now run the 1-5/8″ Heliax cable out, but it was 110 meters short….

The cable was run through the road with plastic pipes for protection.

I am also putting the finishing touches on the working platform at 3 meters height on the King.

The site for the 160M transmit antenna was chosen to have the propagation path run across open waters for more than 180° of the horizon.

The photos are taken at high tide.

The King has risen.

With the help of a 25 ton crawler excavator equipped with a hydraulic rock breaker, a 2.5 m deep hole was broken into the solid rock. The 27 metre long pole weighing 3 tonnes was then inserted into the hole and secured with rocks around the base and temporary guy wires.

New guy anchors will be inserted into the rock and the King will support a 160M transmit vertical antenna before winter.

The photos were taken by Finnbjörn Bjarnason using my camera.

Stan, SF7WT visited TF4M and used the great rhombics for a couple of days.   Unfortunately there was a solar disturbance during his visit causing a massive Aurora and very poor propagation.

Stan is the author of the books ‘Thanks to Amateur Radio’  and ‘Amateur Radio gives you 2 Million Friends‘.

One operating position is fully functional.   The shack has 4 operating positions and each position can choose any available transmit antenna through a 100 kW Strip Line Matrix Switch remotely controlled.

The remaining tasks are to install panels at each operating position to plug in bandpass filters, install wiring for remote antenna switches and power combiners, install computers at positions C and D, wire up PTT control to the Strip Line Matrix switch (to prevent the possibility of hot-switching) and build an indicator panel for the switch.

I will now concentrate on the farm work until autumn before continuing with the project.

I have finished the Beverage antenna project for the time being.

I built 4 bi-directional Beverage antennas ranging from 170m to 380m long.

The antennas are connected into the radio shack via 5000 feet of RG-6 CATV cable entering via a patch panel and fed into a K9AY RAS8x2 matrix antenna switch which then feeds the 8 directions available into two transceivers.

The picture shows the center lines of the main lobe of each antenna direction. The lobes are quite broad especially on the lower frequencies, so I believe I have relatively good coverage.

One operating position is ready – position B which has the control unit for all antennas.   Some work remains, dressing cables, installing computers and building brackets for Bandpass Filters etc.

 

During my Arctic Diamonds presentation on the CCF/OHDXF Ferry Cruise in January, – Tonno, ES5TV asked me whether I had any ”normal”  antennas to compare my rhombics with.   

My answer was a tongue-in-cheek reply to the effect that since I had unlimited space at my disposal, I wasn´t interested in limited space antennas.

A fellow Rhombic owner who indeed has such a comparison antenna sent me the following audio files which demonstrate the difference between the reception of  ”normal ”  antennas and Rhombics.

The first audio file is of TL0A an Amateur Radio Station located  in the Central African Republic, recorded using a huge Log Periodic at 30 meters height.  

Most Radio Amateurs would kill to have such an antenna ! :-)

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The second recording is made 3 minutes later, from the same location, but this time using a  Rhombic antenna to receive TL0A.

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A visual comparison of the two files  says more than a thousand words:

TL0A on LP antenna

TL0A on LP antenna

 

TL0A received with a Rhombic

TL0A received with a Rhombic

 

My Rhombic colleague commented as follows:

”… you will hear what a 30 meter high 6.5 dB gain antenna sounds like with a very wide radiation pattern. It is ideal to pick up all the noise and electrical storms in the equatorial noise zone.

The other recording is 3 minutes later,  with a Rhombic with 20 dB gain, 10 meters high, low take off angle- and a beam width of just 10 degrees. It is not so much that the signal is that much stronger, it is that the noise is that much less. Note the ease with which it is possible to pick up and follow S1 stations that are very weak.

A Rhombic is not just about the gain, it is much more about the noise which you Dont Get…”

 

I rest my case.


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