The mast - the backbone of modern communication
The need for speed and clarity is the most vital factor in all communication. This is especially true for the military. They have used drums, mirrors, pigeons, swallows, signal fires, horses and telegraphy to transmit messages.
The need too communicate is an old heritage. About 35 000 years ago, when mankind made the first cave paintings, one had to go into the cave to read the messages. About 3000 B.C. the cuneiform writing was invented, that was impressed on clay tablets and delivered by messenger in clay envelopes. The postal services were invented about 2000 B.C.
It was Guglielmo Marconi who first demonstrated, a little over a hundred years ago, the possibility to communicate by radio. 1901 he sent a radio message over the Atlantic and seventeen years later another to Australia. In 1906 Reginald Fassenden managed to transmit the human voice through the radio. With radio broadcasting, the radio transmitter entered our homes in the period between 1920 and 1940.
In Sweden, we have two masts in Motala that were used for the early radio communications and one at the Grimeton site that were used for telegraphing over the Atlantic. This site contains six 127-meter high masts that are lined up in a row with 380 meters of space between them for carrying six vertical antenna elements.
In the early beginnings of radio communications, the goal was to find the highest landmark or building and mount the biggest antenna with the highest possible effect to cover as large amount of terrain as possible. Car radios were introduced, and naturally mobile liaison for the police and military.
During World War II, the need for wireless communication increased when most of the main European telegraph cables were sabotaged. As the communication network for both radio and television started growing in Sweden the idea of a few high radio towers, that didn't effectively cover the hilly Swedish terrain, was abandoned. The need was for weatherproof constructions, easy to build, transport and maintain. The standard Swedish mast is most often 3-sided, constructed of hot-dip galvanised steel, built in 6-meter sections and guyed. Measurements were most likely standardized to facilitate transport.
From the birth of mobile (cellular) telephony in the 1970s, demand for usage continued, virtually exploding in 1993 into a mass market. Nowadays we build more ands shorter masts to achieve full coverage and allow the users to move about freely on foot or by car. Modern electronics has drastically lowered the effects and sizes of mobile phones. Will this forest of masts and towers continue to grow on our planet? Or will the latest technology of satellite phones replace our means of communication today?
What is the difference between a mast and a tower?
The simplest explanation is that the mast has guy-lines and the tower stands unsupported. The mast function is to carry antennas, lights or other objects that need to be elevated from the surface. The most common material is hot-dip galvanised steel but it can also be wood, aluminium or fibreglass. The construction is normally supported by hot-dip galvanized steel guy lines on several levels. The height varies a lot. The highest radio masts in Sweden are 325 meters.
A tower has the same function as the mast but it requires less building space because it needs no guy-lines. Most towers are built of steel but concrete is also a common material Both masts and towers require continual maintenance and service, which is easy to overlook, since they tend to be seen as fundamental parts of the environment.