History of Long Range
in the United Kingdom
Long range maritime radio communications in the
United Kingdom started from humble beginnings in 1920.
Broadcasting to ships had been taking
place since the early days of radio; the GPO's (General Post Office) long-wave
stations at Poldhu and Caernarvon had been conducting
two-way traffic with ships within a few hundred miles of
the United Kingdom prior to the First World War. The Marconi Company was, of course, an early leader in developing a number of Coast Radio Stations in Britain and Ireland. Reginald Fessenden had been involved with two way long range radio experiments using both cw (Morse Code) and Voice communications.
However, no long-range system existed
for the maritime service until 1919 when the GPO and the Marconi Wireless
Telegraph Company agreed to convert a redundant Imperial
Wireless chain receiving station at Devizes in Wiltshire for long-range maritime use. Comprising of a
receiver and a 6-Kilowatt valve transmitter, station ''GKT'
was opened for service early
in 1920, with a guaranteed range of 1,500 miles.
The radio officers at 'GKT' were housed
in old army huts, with radiotelegrams being sent to and
received from ships up to 5 days from any British port at
the rate of 11d (just less than 5p) per word. Radio
traffic was keyed to and from the London Central
Telegraph office from the operating station for onward
This two-way "long-range"
service proved to be immensely popular, and by 1924 it
became necessary to expand the station at Devizes to cope
with the increased demand. The GPO constructed a second
long-wave transmitter and built a new receiving station
at Highbridge (near Burnham-on-Sea) in
Somerset, to which most of the radio officers
By 1926, experiments on short wavelengths
had established that world-wide communication could take
place. The GPO installed the first maritime
short-wave transmitter at Devizes, keyed by
operators with receiving equipment at Highbridge that
Initial short-wave tests proved outstandingly successful,
and it became necessary to construct a brand new
transmitting station. This station was to be
located at Portishead, near Bristol, and
thus in 1927 Portishead Radio was born.
Three long-wave transmitters were installed, followed in
1929 by a new short-wave transmitter, ultimately
resulting in the closure of the Devizes station.