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"Wavescan" is a weekly program for long distance radio hobbyists produced by Dr. Adrian M. Peterson, Coordinator of International Relations for Adventist World Radio. AWR carries the program over many of its stations (including shortwave). Adrian Peterson is a highly regarded DXer and radio historian, and often includes features on radio history in his program. We are reproducing those features below, with Dr. Peterson's permission and assistance.
Wavescan 521, December 26, 2004
Radio Anniversary in Australia - Carnarvon
This is Christmas weekend, and we trust that you are enjoying a pleasant occasion, perhaps with family and friends. In our Wavescan program today, we take a look at two events in the radio scene that occurred around the Christmas season way back many years ago.
It was on Christmas Eve thirty years ago, December 24, 1974, that Cyclone Tracy destroyed 80% of the city of Darwin in northern Australia. The modern transmitter base for Radio Australia at Cox Peninsula was disabled and it was very apparent that a new station would be needed, at last on a temporary fill-in basis.
Site studies were conducted in Western Australia and test transmissions were conducted from Gnangara near Perth, using two transmitters at 7.5 kw each. At this stage, three possible locations, all vacant at the time, were given serious consideration, and these were: Gnangara (OTC station established for NASA as a satellite relay station), Dalwallinu (disused American Space Station), and Carnarvon (NASA Satellite Tracking Station).
Finally the facility near Carnarvon was chosen, due mainly to the fact that it was located closest to the desired target areas. Work commenced in mid-1975 on reinforcing the main building against possible cyclone damage and modifying it for use as a shortwave relay station.
New transmitters were also needed quickly. A 250 kw transmitter manufactured in Switzerland by Brown Boveri was installed in the new radio station as the first unit. The second transmitter was a 100 kw Harris from the United States. This unit was already in storage in Adelaide at the time and it had been procured originally to begin a shortwave service for the Northern Territory. The third unit was a 300 kw Thomson transmitter made in France, by essentially the same company that made the first transmitter.
The low, undulating hill on the side of the transmitter building was bulldozed and five towers were installed in the leveled area of red sand to support the four curtain antennas. The entire antenna system was designed so that it could be lowered and tied down in order to minimize damage from an approaching cyclone.
Preliminary test transmissions began from the 250 kw transmitter early in December 1975 and official test broadcasts began a couple of weeks later on December 20. This date was the anniversary of the original launching of Radio Australia 36 years earlier, back in the year 1939. Five years later this unit was taken off the air for a few weeks for design modifications and one of the transmitters at the partially restored facility near Darwin was reactivated temporarily on a fill-in basis.
Programming at this stage came by broadband carrier from Melbourne to Perth, and by ordinary landline up to Carnarvon. A low powered shortwave transmitter at Lyndhurst was also available as an emergency back up for the program feed. When the broadband carrier was finally extended to Carnarvon, the programming line feed for this transmitter was designated as VLK.
The second transmitter was the 100 kW Harris and this unit began test broadcasts on February 15 in the following year, that is 1976. Strangely, just two weeks later, the station was closed temporarily and the antenna system was lowered as a precaution against an approaching cyclone. Three weeks later again, this same transmitter was taken out of service for modification and it did not return to regular service again until November, a period of nearly nine months. This unit was on the air with the program feed designated as VLL.
The third transmitter, rated at 300 kw and designated as VLM, was taken into regular service on May 6, 1984 and it was officially opened a few weeks later.
With the changing winds of fortune, the decision was made to close this so called temporary station at Carnarvon after it had performed 21 years of on air service. The station was finally closed at 1430 UTC on July 31, 1996.
And what happened to the transmitters? The first two transmitters, the 250 kw BBC unit VLK and the 100 kw Harris unit VLL, were removed and sold for scrap. The third unit, the Thomcast VLM at 300 kw, was removed and re-installed at the Darwin radio base where it returned to the air as VLT.
As we mentioned at the beginning of this feature, there are two significant radio events that we are remembering at this season of the year. One was the damaging cyclone in 1974 that disabled the Radio Australia relay station near Darwin in the Northern Territory, and the other was the opening of the replacement station at Carnarvon in Western Australia in 1975.
Interestingly, the Carnarvon station is now gone, and the Darwin station was sold to Voice International and it is now on the air with Christian programming to Asia and with a program relay for Radio Australia. One political party in Australia announced recently that they would plan to buy back the Darwin station and return it to Radio Australia.