Land Mobile Radio


Land Mobile radio system is the common name for communications radio (COM radio), pagers, private radio and mobile phones from the 1940s and later, and for telephones with a frequency range from 27 MHz to 470 MHz and up to 2500 MHz.

On the lowest shelves on the long wall we see three green boxes, a transmitter, receiver and power supply from a police radio from the 1940s. They were so big that they filled the entire luggage compartment. Further up and to the right we see communications radio in several stages of development.

Furthest to the right are more recent appliances - as you see, they became smaller and smaller as the years went on. This size reduction made it possible to produce pocket-sized communication radios, which we can see in the glass show case. The diminishing size was due to increased use of transistors, that came at the end of the 1950-s and replaced the power-hungry radio tubes.

The newest and most modern radio in the show case is made by Danish TP Radio. It has the latest technology in this area. It covers hundreds of channels within a frequency range and can be used for transmitting speech, tones and data.

Use of the earliest communication radios was restricted by a license system to haulage contractors, municipalities, companies and state institutions. But eventually the demand from private individuals became so great that it was made possible to buy private radio, which was used for example in hunting and sport. There are several examples in the show case. The large cabinets furthest to the right are base stations, which are fixed units with a central function in communication radio systems. They usually had a high mast aerial.

Finally, we have mobile phones, whose size also decreased as time went by. In the beginning they were just phones, but our mobile phones these days include computer, camera and much, much more.

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