Thursday 4 November 2010

4-meter band

The 4-metre (70 MHz) band is an amateur radio frequency band in the lower Very High Frequency (VHF) spectrum.

Before World War II, British radio amateurs had been allocated a band at 56 MHz. After the war ended, they were allocated the 5-metre band (58.5 MHz to 60 MHz) instead. This only lasted until 1949, as by then the 5-metre band had been earmarked for BBC Television broadcasts.
In 1956, after several years of intense lobbying by the Radio Society of Great Britain (RSGB), the 4-metre band was allocated to British radio amateurs as a replacement for the old 5-metre band allocation. For several years the 4-metre band allocation was only 200 kHz wide—from 70.2 MHz to 70.4 MHz). It was later extended to today's allocation of 70.0 MHz to 70.5 MHz.
A small number of countries in Europe and Africa have also allocated the 4-metre band to radio amateurs as a result of the decline in VHF television broadcasts on the 4-metre band. Movement away from the old Eastern European VHF FM broadcast band and migration of commercial stations to higher frequencies have led to slow but steady growth in the number of countries where 4-metre operation is permitted.
The 4-metre band has a unique character, because very few countries have an allocation there, very little commercial equipment is available, and therefore most amateurs active on the band are interested in home construction. As a result there is a lot of camaraderie on the band and long ragchews are the norm, as long as there is some local activity

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