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[HCDX] The history of Motala LW
The very first broadcast station in Motala was built 1927 and came into
service the same year on 227 KHz. The power was fascinating 30kW; in
that time one of the strongest broadcast stations in Europe. But soon in
the âbroadcast raceâ in Europe, 30kW wasnât enough and in 1935 a new
150kW-transmitter is installed, even this time a transmitter from
Marconi. Cost: 1.25 Million SEK (35 Million SEK January 2005). The old
30kW stands as a back-up if something would happen with the
150kW-transmitter. The plans in the 50âs to replace this old and
ineffective transmitter resulted in a complete new transmitter 15km SE
of Motala. In the early 50âs the chief master of Engineering at the
Swedish Telecommunications Administration; Folke StandÃn, had developed
an unique antenna system: An antenna system shaped as a circle with one
central antenna in the middle of the circle and five antennas standing
630m from the central antenna. It would result in a better ground wave
with antenna system even though it sent out a space wave with 45Ë angel
but it shouldnât have any affection.
The old 150kW transmitter in central Motala forced staff day and night.
The efficiency of the transmitter laid only on 22% and fading occurred
already on a distance of 80km. With the new station the fading zone
would be put out as far as approx 200km. Due to the situation in the
world in the 50âs - The Cold War â the transmitter hall was shaped as a
bunker with 1,4m thick concrete walls with no windows. The central
antenna stood beside the âbunkerâ. The height of the antennas was 250m
for the central antenna and 200m for the âcircle antennasâ. This new
broadcast station became equipped with 2x300kW Compagine FranÃais â
Thomson Houston (CFTH) transmitters with an efficiency of 62%! These
transmitters could be used single or double with a max output power of
600kW. Normally one transmitter would be used and the other in stand-by
mode, ready to be taken in use if something would happen with the first
transmitter. The hole inside of the bunker was lined with cupper plates
â just like Faradayâs Cage. The big differ with this new station
compared to the old one, except of the power etc. it was totally
automatized and had a reserve power plant, a V8 diesel engine on 1100hp.
In 1961 the whole station was ready to be put in service and the old
150kW in central Motala would be retired for ever. H.R.H Prince Bertil
inaugurated the station 8.th May 1962. Total cost: 15 million SEK (139
million SEK January 2005). The new station was in a question. Many
wondered if it was necessary to build a new huge station when one could
get several FM-transmitters for the same price. The spokesmen defended
their arguments with many persons still only had receivers with long-
and medium wave. But everything wasnât alright. Shortly after the
transmitter was put into service, an East German station started up from
East Berlin and laid just 6 KHz below Motalaâs frequency 191 KHz. This
resulted in heavy interference but after a while SDDR/Stimme Der DDR
shut down.
More problems were to come. In July 1970 during a thunderstorm, the
lightning strikes the central antenna, shatters an isolator and cut off
a stay resulting in the central antenna crashes right over the bunker -
totally demolished. The roof on the bunker manages the crash with only
astonishing light damage. Until a new feeder is connected to one of the
circle antennas, the power is reduced to 100 kW. The central antenna was
never rebuilt. When the oil crises hit the world in 1974 the power is
temporary reduced to only 250kW. During the 70âs and early 80âs when
most of the old AM-transmitters were shut down and scraped, Motala was
upgraded instead but the listeners continued to leave the long- and
medium wave in favour of the more comfortable FM-mode. The maintaining
and costs rose. The Government had already plans in 1980 to shut down
Motala but after massive protests the station could live a few years
more. To achieve the new purpose from SR the antenna system was rebuilt
to a certain beam towards Copenhagen and Helsinki without increasing the
reception in Oslo. It achieves with only two of five antennas.
A new kind of more effective modulation, processed sound, starts to be
in use in 1983. The temperature of the modulation transformer lays
nearly the alarm limit and more effective like this, it canât be. As a
result of the wavelength plan in Geneva in 1979, the frequency is
changed to 189 KHz in 1986. This was the beginning of the end for
Motala. Soldiers from the army blasted three of the antennas in the
winter 1987 while it still was cold and ground frost. Now the final shut
down is at hand, the Swedish Telecom decided to make a study how many
persons who really listened to the station.
In 1989 the result came â approx 200 listeners and in 1990 the reserve
power plant crashed â a piston went right through the top block. Swedish
Telecom asked for 3 million SEK to repair the reserve power plant and
maintain the stays on two of the remaining antennas.
The Swedish Telecom didnât find any economy to continue broadcast on
long wave with only 200 listeners. The congress and the government had
no objections to draw back the money for maintain, 1.1 million SEK
annual, and the date for the final shut down was decided to 30.th
November 1991.
With a special program the last hour ending with the Swedish national
anthem, an almost 65 year long epoch was at end.
Sadly the two remaining antennas were blasted in 1994 and in 1995. Still
the bunker with two intact transmitter remains. Nowadays the bunker is
owned by a private person and can be visited after reserving time via
the broadcasting museum in central Motala, hosting in the old
broadcasting station â right where it once started in 1927! Note the
station could be listened in the Baltic Countries, Swedish speaking
parts of Finland, Norway, Denmark, parts of Germany and halfway to the UK.
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