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| Deutsche Welle - Trincomalee, Sri Lanka |
It was back in
the early part of the year 1985 that our DX editor Adrian Peterson teamed up
with the well-known shortwave radio personality Jonathan Marks from Radio
Netherlands and his wife Marian for a five hour journey by car across the
island of Sri Lanka from Colombo to Trincomalee. The purpose for this journey through the
sometimes-dangerous insurgency areas was for a visit to what was the Deutsche
Welle relay station which had been installed in what had previously been a
Royal Navy wireless communication station.
Following our inspection of the shortwave and mediumwave equipment in
that very modern international radio broadcasting station, our tour guide at
Deutsche Welle took us out into the massive antenna field. He explained that there were occasions when a
tribe of wild Asian Elephants had broken down the protective fence surrounding
the antenna field and they then encroached onto the station property, sometimes
causing damage to an aerial system.
Then
too he added, from time to time, a troop of wild monkeys has come parading
through the area, swinging from the structural wires of the huge curtain
antenna systems, though thus far, they had caused very little damage, and
neither had any of them become electrocuted.
We should add that SLBC, the Sri Lanka Broadcasting Corporation, now
operates the Trincomalee radio station, and that this our DX program Wavescan
is regularly heard on shortwave from one of their four powerful 250 kW
transmitters.
Then too, VOH the Voice of Hope in Zambia Africa has experienced a
similar problem with monkeys invading their station property. There are many wild monkeys that live in the
trees surrounding the antenna field of their isolated shortwave station. Sometimes they get so bold that they come
right down onto the ground surrounding the transmitter buildings looking for
food.
A few months ago, the engineering staff discovered that the air
temperature in the main transmitter building itself was getting dangerously
high; and in addition, the industrial air conditioning unit was no longer
working.
When they investigated, they
found that much of the insulating material surrounding the ducts from the
compressors outside the back of the building had been stripped bare by the
monkeys; and in addition, some of the electrical wiring had been broken off
also. When all had been repaired and
replaced, they were careful to ensure that all of the outer surfaces were
monkey-proofed.
Over in nearby India, Manosij Guha tells us in the 2002 edition of Larry
Magne’s now defunct annual publication
Passport to World Band Radio that a shortwave radio station in his country had
a similar animal problem. Manosij tells
us that All India Radio AIR established a shortwave relay station near the
small town of Aligarh some 60 miles east of New Delhi in 1971.
Initially this station, on its estate of more than 800 acres, contained
two shortwave transmitters at 250 kW each, together with 39 antenna systems and
15 miles of feeder lines. Manosij Guha
stated that on several occasions nilgais, the large brown Indian antelope, have
invaded the antenna farm and been electrocuted in the antenna field.
On two separate occasions in two widely separated countries, sheep have
been the culprit in causing strange sounds in a radio transmission.
The now silent shortwave station operated by Radio Australia in Victoria
was installed on a property of 600 acres located at 490 Verney Road in what is
now North Shepparton. Although the
property is located in what is described as sheep grazing country, currently
the area is becoming somewhat built up with local housing.
At the height of its operational capacity, Radio Australia Shepparton
contained seven shortwave transmitters; 4 @ 100 kW, 2 @ 50 kW, and 1 @ 10
kW. On the antenna farm were 15 steel
towers standing 210 ft high supporting 24 curtain antennas, with an additional four
rhombic antennas for use in emergency occasions.
In its earlier usage in the postwar years, the growth of high grass in
the antenna field became a problem due to the likelihood of fires during the
hot dry summer. So a flock of 850 sheep
were obtained, Border Leicester cross with Merino, and they kept the grass
down.
On one occasion way back, apparently there was a meter in the
transmitter hall at Shepparton that gave a strange erratic reading. When the staff investigated outside, they
discovered that one of the sheep was scratching an itch by rubbing itself
against a feeder line pole.
Back towards the end of the year 1993, a similar event occurred in
England. It was reported that a
government communication radio station at Scarborough in Yorkshire, Northern
England was emitting strange high frequency noises. An investigation revealed that sheep were
rubbing against what they described as an aerial pole.
Back towards the end of the year 1993, Jonathan Marks (again!) in his DX
program Media Network from Radio Netherlands shortwave told the story of how a
school of shrimp put their station on the island of Bonaire in the Caribbean
off the air. The concentration of shrimp
in the water pond clogged the water intake for the cooling system and the station
had to be closed until the fish were cleared from the cooling equipment. The abundance of shrimp in the wetlands and
shoreland areas of Bonaire attracts the Pink Flamingo for which the island is
quite famous.
The March 1999 issue of Contact,
the monthly magazine from the World DX Club in England, tells us another interesting story. They state that the National Rivers Authority
in Great Britain inserted a tiny radio transmitter into 450 salmon fish so that
they could be tracked as they migrate up the River Hirnant in Wales.
At one stage, their mobile radio detector indicated that one of these
fish had leaped out of the water and was moving across dry land. The authorities tracked the mobile salmon
with their radio receiver to the home of a fisherman, who confessed that he had
been fishing without a license.
And finally, one for the birds!
This item happened back during the 1940s, and it is taken from a 1995
issue of the American radio journal, Radio World.
The incident that we refer to occurred at mediumwave station WBAA, which
is still located at Purdue University in West Lafayette, Indiana. At the time, the station was located in the
Electrical Engineering Building, and the antenna was suspended between two
towers that were part of the steel framework of the building. These towers extended 88 feet above the top
of the building and they supported a cage antenna made up of several parallel
conductors each about seven inches apart.
One summer afternoon back in the 1940s at about four o’clock, the meter on the transmitter
indicated a gradual change in the antenna current. The operator checked all systems, and
everything seemed to be OK. After half
an hour with very low antenna readings, the meter reading began to improve
until it slowly returned back to normal.
Next day, and on the following days, always at about the same time, the
antenna reading began to deteriorate to a dangerously low level, and then
gradually return to normal. Now on
Sundays, station WBAA was off the air, and on one occasion the operator
happened to drive past the station at about the same time, four o’clock in the afternoon.
He was amazed to discover that the antenna was literally covered with
Blackbirds, perched on the cross bars from one end of the antenna to the
other. In spite of the heavy
construction of the antenna, it was sagging noticeably, enough to change the
level of capacitance with the ground.
In addition, the effective increase in the size of the antenna with all
of the birds upon it changed the impedance factor of the antenna. This then was the cause for the low meter
readings and the deterioration of the level of the transmitted signal.
Indeed, that cage antenna was actually … a bird cage antenna!
(AWR Wavescan/NWS 493)
