Station Profile - Medium wave in Stuttgart and nothern Baden-Württemberg

Written by Stefan Greve

Broadcasts from Stuttgart started on 10 May 1924. The station was called "Süddeutsche Rundfunk AG" (SÜRAG), though the name was often shortened to "Südfunk Stuttgart".
The first transmitter was Stuttgart-Pragsattel (686 kHz, 0.25 kW).
It was replaced by Stuttgart-Degerloch starts broadcasting on 790 kHz with 1.5 kW.
Stuttgart-Degerloch starts broadcasting on 790 kHz with 1.5 kW.
The frequency was changed to 802 kHz (Brussels Plan, 1929), then to 833 kHz (Prague Plan, 1930).

On 21 November 1930, Germany's first high power mediumwave transmitter went on air in Mühlacker (located between Stuttgart and Karlsruhe), with 60 kW on 833 kHz.
On 20 October 1933, Mühlacker was closed for reconstruction, and Stuttgart-Degerloch was reactivated.
When the wave plan of Lucerne became effective on 1 January 1934, Mühlacker returned to air with 100 kW on 574 kHz.
(One of the two masts of the Degerloch transmitter site was used for FM and TV twenty years later.)

SÜRAG became "Reichssender Stuttgart" on 1 April 1934.
A second 100 kW-transmitter was installed in Mühlacker on 15 March 1940.
On 6 April 1945, the antenna was destroyed by the SS.

From Radio Stuttgart to SWR

Mühlacker I (574 kHz, 100 kW) returned to air on 3 June 1945, under American control. The new "Radio Stuttgart" was the broadcaster for northern part of Württemberg and Baden (the southern parts belonged to the French zone).
On 22 July 1949, the station returned under German control and was renamed "Süddeutscher Rundfunk" (SDR).
(Since September 14, 1947, Radio Stuttgart was also on shortwave. The transmitter in Mühlacker used 6180 kHz until 1950, then moved to 6030 kHz. Soon the power was raised from 1 kW to 10 kW, and to 20 kW in 1951.)

Mühlacker II (1249 kHz, 100 kW) was used by AFN since 28 November 1945. AFN Stuttgart shared this frequency with AFN Munich (via München-Ismaning II).

According to Copenhagen wave plan, the stations of the American Zone (Frankfurt, München, Stuttgart, RIAS Berlin and several transmitters of lower power) had to share 989 kHz and 1602 kHz. Each frequency was limited to 105 kW in total, and not more than 70 kW per transmitter. For AFN, 1554 kHz was planned.
With permission of the American Military Administration, most stations ignored the plan.
Though Stuttgart's frequency (now 575 kHz) was given exclusively to Riga, SDR remained on it. It took four years (until 21 April 1954), that SDR somehow obeyed the plan and screened the transmissions towards Riga at night.

AFN Stuttgart briefly used 1061 kHz, before moving to 1106 kHz. The frequency was no longer shared with Munich.
However, when AFN Munich lost its frequency (548 kHz) to Deutschlandfunk in 1962, AFN Stuttgart had to relinquish 1106 kHz to the more important station in München-Ismaning.
AFN Stuttgart had to use the transmitter Hirschlanden (1142 kHz, 10 kW) in the north of Stuttgart instead.

SDR shared 575 kHz not only with Riga, but also with stations in the GDR (first Potsdam, then briefly Burg and finally, since 1954, Leipzig).
On 22 April 1966, the power was raised to 300 kW. (Before, it had been raised to 150 kW in 1959 and combined with the former AFN transmitter to a total of 250 kW in 1964.)

The Geneva Waveplan, effective in 1978, didn't really change the situation. Though Stuttgart-Mühlacker (576 kHz, 300 kW) was now "legal", it shared it's frequency with even more powerful stations. At night, it had to be screened towards 30°-50° (Riga) and 106°-122° (Vidin, Bulgaria). GDR also kept the frequency, now for Schwerin-Wöbbelin (250 kW, directed).

Schwerin was switched of in 1992 (only briefly reactivated in 1999). On 1 January 1996, the power of Stuttgart-Mühlacker was reduced to 100 kW.
(The shortwave station on 6030 kHz ceased broadcasting on 17 October 1994.)

Since 1998, Süddeutscher Rundfunk and Südwestfunk (the broadcaster of the former French Zone) are merged into "Südwestrundfunk" (SWR). Mühlacker now carries the information programme "SWR ContRa".

It was planned to use a modern transmitter (684 kHz, 50 kW, daytime only, from the closed RIAS relay station Hof) in Mühlacker after 1995. It should carry "Deutschlandradio Berlin", but never went on air.


Relay stations

Until 1950, Mühlacker covered the whole territory of SDR (and more). Then the interferences made several additional transmitters necessary.
The first was Ulm-Jungingen (1169 kHz, 1 kW) on 24 December 1950. The power was raised to 3 kW in the mid-1950 and to 5 kW in the early 1960s.
Next was Bad Mergentheim (890 kHz, 1 kW) on January 28, 1951. Circa 1953 the power was raised to 3 kW, and the frequency changed to 1412 kHz.
Heidelberg-Dossenheim (998 kHz, 5 kW) followed on 1 September 1951. It was planned to raise the power to 20 kW, but it became only 8 kW in the early 1950s and 10 kW circa 1959.
Finally, Heilbronn-Obereisesheim (1169 kHz, 8 kW) went on air on 24 December 1952. It was also raised to 10 kW around 1959.

In 1978, Heidelberg, Heilbronn and Ulm switched to 711 kHz, all with 5 kW. Bad Mergentheim (3 kW) remained on 1413 kHz. In the late 1980s it's frequency was changed to 711 kHz too.
Bad Mergentheim was closed in 1999, Heidelberg followed in May 2004.
Heilbronn and Ulm are still active.

These still could not provide full mediumwave coverage everywhere, so a lot of low power transmitters (1484 kHz, 0.2 kW) came on air.
The first was Wertheim (18 Dec 1954), followed by Buchen-Walldürn (May 1, 1955, on 998 kHz), Heidenheim, Crailsheim, Schwäbisch Hall (1956), Mosbach, Eberbach, Bopfingen, Ellwangen, Adelsheim, Gerabronn, Giengen (1957), Kirchberg, Neresheim (1958) and Külsheim (1959).
In the mid-1960s, Crailsheim, Eberbach, Ellwangen, Gerabronn, Giengen, Kirchberg, Külsheim, Mosbach, Neresheim and Schwäbisch Hall are closed.

In 1978 they switched to 711 kHz (Bopfingen, Wertheim), 1413 kHz (Buchen-Walldürn, Heidenheim) or 1485 kHz (Adelsheim).
When Bad Mergentheim moved to 711 kHz, the low power frequencies are rearanged: 711 kHz Bopfingen, 1413 kHz Heidenheim and Wertheim, 1485 kHz Adelsheim and Buchen-Walldürn.
None of the 0.2 kW-transmitters is active anymore.

AFN

In addition to the main transmitter in Mühlacker and later Hirschlanden, AFN Stuttgart used some low power relays.
The first was Heidelberg (1500 kHz, 0.35 kW) on 22 October 1948. It was changed to 1169 kHz in 1950.
Circa 1951 the power was raised to 1 kW, briefly on 1223 kHz. From circa 1953 to 1978 the frequency was 1304 kHz.

Wertheim followed in the late 1950s, Göppingen in the early 1960s (both on 1304 kHz with 0.25 kW).
Circa 1964 Göppingen switched to 1142 kHz, and Ulm (1142 kHz, 1 kW) started.
Two years later Karlsruhe (1034 kHz, 1 kW) and Crailsheim (1394 kHz, 0.25 kW) followed.

In 1978, Crailsheim went to 1485 kHz, Stuttgart-Hirschlanden and all other transmitters used 1143 kHz.
(Ulm was in the Geneva Plan, but probably already closed at this point.)

Today Stuttgart-Hirschlanden (10 kW) and Heidelberg-Wieblingen (1 kW) carry "AFN Power Network" on 1143 kHz, all other transmitters are closed since the mid-1990s.

A second transmitter in Stuttgart-Hirschlanden (738 kHz, 5 kW) was used for private commercial radio.
First "Mega-Radio" was active from 16 January 2002 to 4 April 2003.
From 15 August 2005 to May 2008 the transmitter was used by "Truck Radio".
Now the station is silent again.


Main sources:
Internationales Handbuch für Rundfunk und Fernsehen
World Radio (TV) Handbook
http://www.asamnet.de/~bienerhj/rundfunk-hs.html