Tuesday, March 03, 2020

The Grand Wireless Station at Monte Grande


Another great radio nostalgia story from Wavescan. Thanks to AWR.

      Construction work on the world’s largest wireless station, as it was touted at the time, began a little over one hundred years ago in the year 1918.  However, due to the Great War and its aftermath  over in continental Europe, progress on the work was quite slow.  Initially, the Marconi company in England began the preparatory work, but due to the total size of the completed project, a consortium group including other wireless manufacturing companies was formed.

A combined property of 1200 acres located on the south side of Buenos Aries and 25 miles from the city center was obtained as the location for the Monte Grande longwave wireless station.  Two powerful alternators at 400 kW each were installed, and electricity with 800 kW at 12,500 volts, was fed into the station from the city generating plant. 

The two alternators were capable of transmissions in the longwave spectrum, running from around 18 kHz up to about 72 kHz.  In regular usage, one transmitting alternator was on the air while the other was maintained in standby mode.

The massive antenna system in total was nearly two miles long, and it was formed in the shape of the English capital letter T.  It was supported on ten towers in pairs each 680 ft tall and spaced at nearly a quarter mile apart.  These towers were imported from CTSF in France and from Telefunken in Germany.

The 16 wire aerial system was supported at 200 places by cross wires incorporating the use of a thousand insulators.  The steel cables that supported the aerial wires were installed with insulated rollers, and the aerial wires were weighted at each end with weights at 88 pounds each, thus allowing for compensation in wire lengths due to variations in the local temperature.  There was a complicated double counterpoise system with a buried network of wires, as well as another system of wires, 30 ft above ground level.

The Monte Grande Wireless Station was officially opened in a formal ceremony on Thursday January 24, 1924, in the presence of the president of Argentina, Senor Marcelo Torcuato de Alvear.  Next day, this new and grand wireless station, with the international call letters LPZ, began Morse Code communication with similarly high powered longwave wireless stations in London, Paris, Berlin and New York.

During the early 1920's, the communication scene throughout the world was in transition from wireless to radio, and thus, in 1925, just one year after the opening of the Monte Grande wireless station, two American made RCA shortwave transmitters rated at 20 kW each were installed at the same location.  In this way, voice communication began to take over from communication by Morse Code.

Give six more years (1931), and the two hefty wireless alternators were decommissioned and a bevy of additional shortwave transmitters was installed.  At the beginning of the European War in 1939, several shortwave transmitters were in use at Transradio Monte Grande, ranging in power from 1 kW to 125 kW.   An additional 100 kW transmitter was installed in November of that same year (1939).

Beginning in the mid 1930s, the Monte Grande radio station was often noted in the United States and elsewhere with the broadcast of radio programming.  The transmitters generally in use for the relay of programming from local mediumwave stations were rated at 10 kW and 20 kW.

       Sometimes a shortwave transmitter was in use as a program link from a Buenos Aires mediumwave station to an upcountry mediumwave station, and on other occasions the purpose was for the relay of mediumwave programming for network rebroadcast in the United States as well as for direct reception worldwide. 

      Radio station LSX at Monte Grande was often heard with a program broadcast at 10 kW on 10350 kHz.  This station was recognized and appreciated internationally as a reliable verifier of listener reception reports. In 1970, the official telecommunication concession ended and the Grand Wireless station LPZ-LSX at Monte Grande was closed, and abandoned.  Several other shortwave stations in Argentina took over the various services previously on the air at Monte Grande.

In 2011, the Monte Grande location was declared a Nature Reserve as Laguna de Rocha (Rocky Lagoon), and much of the abandoned radio structure is still in place.  The front of the huge main building still stands intact, though a picture at the back of the building shows nothing but wrecked debris.  Some antenna towers are also still standing.

Two additional radio buildings on the same site are also abandoned, though they are still in good condition.  These two structures were the transmitter buildings for two mediumwave stations, Radio Splendid LR4 currently with 25 kW on 990 kHz, and Radio Excelsior LR5 with likewise currently 60 kW on 910 kHz.

Transradio Receiving Stations
The first receiver station for Transradio Monte Grande in Argentina was located at the outer suburban Villa Elisa, some 20 miles from downtown Buenos Aires, and 25 miles from the transmitter station.  Two flat top multi-wire aerial systems were installed, thus ensuring reception from both Europe and the United States. 

A bank of electrically operated receivers was installed in a specially constructed building.  It was back in 1924 that this receiver station was taken into service, along with the transmitter facility at Monte Grande.  These days, this Transradio property is serving the local community as an Ecological Reserve, a Nature Park.

During the year 1935, a replacement receiver station was installed on a property at suburban San Martin known as the La Dora Farm.  This receiver station was closed in 1970, along with the Monte Grande transmitter site, and since then this property has also been taken over as an Ecological Reserve.

According to information in print in Argentina, all three Transradio properties (transmitter site at Monte Grande, early receiver site at Villa Elisa, subsequent receiver site at San Martin); all, strangely enough, have been taken over by the local communities for public use as Nature Parks.
(AWR-Wavescan/NWS 575-01  Mar 2020)