Currently viewing the tag: "antennas"

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.

The open wire feeders are getting rather slack.  This causes the wires to twist together during high winds.  I had noticed a slightly higher SWR and some scratching noises while receiving on the USA Rhombic.

I had to examine the entire run of the antenna feeder and the antenna itself.  Looking up into the bright sky is rather difficult for me due to the condition of my left eye after the accident, but with a good pair of binoculars it only took me about one hour to find and correct the problem.
I guess some maintenance is called for before winter…

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.

I have acquired a few rather large insulators.   I believe I will use them for the 160M transmit antenna.

The insulator in the photos is 150cm long and weighs more than 30kg.

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.

 

While on TDY in the Republic of Abkhazia, I had the opportunity to do some work on the Sukhumi TV tower.   The tower had been damaged by shelling with one of the four legs shot through near ground level.   A rather frightening structure.

The last picture shows the top of the Microwave tower in Ochamchira.

I have begun the work of re-building the Vertical antenna recovered last winter.   Today I installed the two tonne concrete block foundation and moved the 6 concrete anchor blocks into the area.

The XYL is not happy with the location chosen for the antenna.  I will have to find another spot to put it… 8-)

Start Slide Show with PicLens Lite PicLens

I have 4 of these couplers made by E.F. Johnson, in my possession.

My guess is that they are meant for M.F. and may have been designed to feed a 500 kHz Vertical with open wire feeders.

Perhaps I will put them into service again one day, if TF amateurs receive access to the 600 meter band.

 

I have a few of these high power relays, but the relay voltage is unknown and it is not marked.

The relay coil measures 10 ohms.

I intend to use them for Rhombic direction switching.

Measurements with a variac revealed that the relay switches around 60 VAC and is comfortable at 110VAC drawing 0.8A without coil heating.

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