Station Profile - Motala 227 kHz

Written by Christian Stödberg

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 “broadcast race” in Europe, 30kW wasn’t enough and in 1935 a new 150kW-transmitter is installed, even this time a transmitter from Marconi.

range of Motala transmitter

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 50’s to replace this old and ineffective transmitter resulted in a complete new transmitter 15km SE of Motala. In the early 50’s the chief master of Engineering at the Swedish Telecommunications Administration; Folke Standén, 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 45° angel but it shouldn’t have any affection.

ring system at MotalaThe 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 50’s - The Cold War – the transmitter hall was shaped as a bunker with 1.4m thick concrete walls with no windows. The central antenna stood beside the “bunker”. The height of the antennas was 250m for the central antenna and 200m for the “circle antennas”. This new broadcast station became equipped with 2x300kW Compagine Français – Thomson Houston 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 – just like Faraday’s 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 8th 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 wasn’t alright. Shortly after the transmitter was put into service, an East German station started up from East Berlin and laid just 6 KHz below Motala’s 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 70’s and early 80’s 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.

Motala transmitterA 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 can’t 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 – approx 200 listeners and in 1990 the reserve power plant crashed – 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 didn’t 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 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 – 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.

QSL from Motala