Inselsberg transmitter

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Inselsberg transmitter
Radio transmission point Tabarz 1
Image of the object
Basic data
Place: Big island mountain near Winterstein
Country: Thuringia
Country: Germany
Altitude : 909  m above sea level NN
Coordinates: 50 ° 51 '5.2 "  N , 10 ° 27' 55.4"  E
Use: Telecommunications tower , broadcasting station
Accessibility: Transmission tower not open to the public
Owner : German radio tower
Tower data
Construction time : 1972-1974
Operating time: since 1974
Total height : 126.2  m
Data on the transmission system
Last modification (transmitter) : September 2015
Waveband : FM transmitter
Radio : VHF broadcasting
Send types: DVB-T, DAB , mobile radio , directional radio
Position map
Transmitter Inselsberg (Thuringia)
Inselsberg transmitter
Inselsberg transmitter
Localization of Thuringia in Germany

The Inselsberg transmitter is a transmission system for VHF and digital television on the Großer Inselsberg in the Thuringian Forest with two transmission towers that were built in 1939 and 1974. Only the transmission tower built in 1974 is used as such. The tower, built in 1939, no longer has an antenna. Among other things, it houses an exhibition on the development of telecommunications and radio; he also carries a solar system.

history

As early as 1937, employees of the Deutsche Reichspost began with technical experiments around the Großer Inselsberg. This work lasted until 1938, at the same time an engineering office was commissioned with the construction of a transmission tower. The foundation stone was laid on April 15, 1939, and the shell of the building had already been completed by the start of the war in September 1939. 200 fitters and workers were working day and night shifts on the construction site. This building, erected in 1939, is a 43-meter-high, free-standing cylindrical tower made of reinforced concrete, which was used as a radio transmission and monitoring station for military purposes until the end of the war. The site was cleared in April 1945 and was left unattended for months, which led to looting. With the approval of the Russian military administration, a branch of the German Weather Service was built on the 8th floor , initially approved as a provisional measuring and observation center.

After that, the tower served as a lookout tower for a few years. In 1952, the repair work began on behalf of the Ministry for Post and Telecommunications of the GDR . As early as May 1953, a first 250 watt VHF transmitter on the fifth floor was put into operation with a test program. To supply it, a new water and power line had to be laid to the tower. The transmitter also received two emergency power generators to bridge shutdown periods and technical failures. The regular transmission of the first Thuringian VHF transmitter began on June 15, 1953 on the transmission frequency 94 megahertz. As early as December 1953, the transmission power was increased by 1 kilowatt through technical improvements to the system, which increased the range. In December 1954 the television station was transported up the mountain.

Since 1955, extensive structural preparations for the construction of a new antenna support have been tackled. In the tower, the coal heating was expanded and an oil heating installed, now all transmission rooms could be equipped with air conditioning. An inconspicuous low-rise building was built on the edge of the post office as accommodation with 18 residential units for operating and maintenance staff.

In 1967 the GDR Council of Ministers approved the provision of the transmitter components and the 126 m high antenna system for the second television program on the Inselsberg. The construction project, coupled with a general technical overhaul of the transmission technology on the island's mountain, was estimated at 25.5 million GDR marks.

From 1957 to 1989 the tower, like the Gerbrandytoren , carried a 50 meter high antenna mast on its top, which was guyed to the ground. The total height was thus 93 meters. Various transmission antennas for radio and television were installed on the antenna mast. Today this antenna mast has been dismantled, instead only small antennas for cellular radio adorn its top. Because of its cylindrical shape, the tower is also nicknamed the "thermos bottle".

A second tower was built in the second half of the 1950s in connection with the construction of the narrow-band radio link of the SED Central Committee. It was used to establish radio links between the southern districts of the GDR and, in the 1960s, to the party's district leadership.

On August 15, 1972, the assembly and welding work for the so-called Bock construction began - the base frame of the new transmission tower. All other parts of the transmission tower were pushed up from below using four existing lifting devices, the top of the carrier tower first. A ruby laser was used as a leveling aid . The shell of the antenna tower was completed on November 28, 1972, and after a technical inspection the aluminum cladding was installed. On July 26, 1974, the station started operating.

The new transmission tower, built in 1974, is a free-standing 126.2 meter high tubular steel tower that stands on four feet. This tower, which in its construction corresponds to the new transmission tower erected on the Brocken at about the same time , today has directional antennas above its foot on three platforms and transmission antennas for VHF radio and digital television ( DVB-T ) in the upper part of its construction . The TV antennas are protected by GRP sheaths .

In 1991, the pendulum absorber in the top of the transmission tower was replaced using the Mil Mi-8 transport helicopter from Berliner Spezialflug (BSF).

In favor of the switch to DVB-T , the analog TV channels ARD (100 kW on channel 5) and MDR television (500 kW on channel 31) were discontinued on July 1, 2008.

Range

The transmitter Inselsberg has a topographical location on the northern edge of the Thuringian Forest, which is exposed for a long range. In addition to western and central Thuringia, the transmission area extends from northern Baden-Württemberg over all of northern Bavaria to North Rhine-Westphalia . The programs broadcast by the Großer Inselsberg can also be received in parts of Hesse , Saxony , Saxony-Anhalt and Lower Saxony . In the north, the transmission area ends in Lower Saxony near Hanover .

The frequency with the longest range is 90.2 MHz due to less interference from neighboring frequencies. You can hear them beyond the regular catchment area from Hanover via Halle / Leipzig, Saalfeld, northern Franconia as well as in Frankfurt and in the central Hessian mountainous region.

Frequencies and Programs

Analog radio ( FM )

In the case of directed radiation, the main radiation directions are given in degrees in the antenna diagram.

Frequency  
(MHz)
program RDS PS RDS PI Regionalization ERP  
(kW)
Antenna pattern
round (ND) / directional (D)
Polarization
horizontal (H) / vertical (V)
92.5 MDR Thuringia MDR_THUE D4F1 Erfurt 100 ND H
90.2 MDR JUMP MDR_JUMP D3C2 - 100 ND H
87.9 MDR culture __MDR___ / _KULTUR_ D3C3 - 60 ND H
97.2 Deutschlandfunk culture Dlf_Kult D220 - 100 ND H
102.2 Antenna Thuringia AT-WEST_
ANT.THUE
D4F8 (regional), 
D3F8
west 100 ND H
104.2 Landeswelle Thuringia COUNTRY D4F9 (regional), 
D3F9
west 100 D (310 ° -110 °, 170 ° -240 °) H

Digital radio ( DAB )

Former, directional transmitting antenna VHF

From January 4, 2010 to December 11, 2014, DAB ran in Thuringia as an isolated solution (DAB channel 12B). As a result, some transmitter sites were switched off. On August 1, 2011, further MDR radio programs were switched to the ensemble.
On April 2, 2013, the DAB transmission system was removed from the existing old network DAB channel 12B. The DAB channel 9C (regional multiplex of the MDR) and reduced transmission power in single- frequency
operation with the transmitter Weimar (Ettersberg) took place . At the same time, the old transmission system will continue to be used for broadcasting DAB channel 5C (nationwide multiplex).

The currently available transmitting antenna only allows directional radiation in the direction of west-north-east-south-east.
As part of the restructuring to a uniform frequency for Thuringia, in December 2014, DAB block 9C was switched to block 8B.

DAB is broadcast in vertical polarization and in single-frequency mode with other transmitters.

block Programs
(data services)
ERP  
(kW)
Antenna diagram
round (ND),
directional (D)
Polarization
horizontal (H) /
vertical (V)
Single frequency network (SFN)
5C
DR Germany
(D__00188)
DAB + block of media broadcast: 5 ND V
8B
Thuringia
(D__00229)
DAB + block of the MDR : 10 ND V Bleßberg (Sonneberg) , Dingelstädt , Gera (Langenberg) , Inselsberg , Jena (Oßmaritz) , Kreuzberg , Kulpenberg , Lobenstein (Sieglitzberg) , Saalfeld (Remda) , Suhl (Erleshügel) , Weimar (Ettersberg)


Former DAB multiplex Kanal 12B (Thuringia) January 4, 2010 to December 11, 2014
block Programs
(data services)
ERP  
(kW)
Antenna diagram
round (ND),
directional (D)
Polarization
horizontal (H) /
vertical (V)
Single frequency network (SFN)
12B 
K12 Thue
(D__00015)
0.5 D. V Gera-Ronneburg , Ilmenau (Kickelhahn), transmitter Inselsberg, Jena (Oßmaritz-Cospoth), Lobenstein (Sieglitzberg), Suhl (Erleshügel)
former DAB multiplex channel 9C (Thuringia) until December 11, 2014
block Programs
(data services)
ERP  
(kW)
Antenna diagram
round (ND),
directional (D)
Polarization
horizontal (H) /
vertical (V)
9C
Thuringia
(D__00233)
5
(plan 10)
D
(plan ND)
V

Digital television (DVB-T2 HD)

The conversion of the transmitter Island mountain on the standard DVB-T2 HD with HEVC image coding was on 28 November 2018. On three channels is a program package ever ( Bouquet ), partly in simulcast , sent (Single Frequency Network) with other sites.

freenet TV , the fee-based DVB-T2 HD platform from Media Broadcast , is not broadcast here.

channel Frequency (  
MHz)
Multiplex Programs in multiplex ERP  
(kW)
Antenna pattern
/ round (ND)
directed (D)
Polarization
horizontal (H) /
vertical (V)
Modulation method FEC Guard interval Bit rate  
(Mbit / s)
Single frequency network (SFN)
27 522 MDR 1 (ARD) 50 ND V 64-QAM 3/5 19/256 23.6 Erfurt-Windischholzhausen , Weimar (Großer Ettersberg) , Jena (Kernberge) , Gera , Inselsberg
39 618 MDR 2 (ARD) 50 ND V 64-QAM 3/5 19/256 23.6 Inselsberg
41 634 Substream 0:

ZDF

( ZDFmobil )

Substream 1: MEDIA BROADCAST

Substream 0:

Substream 1:

50 ND V 64-QAM 3/5 19/128 22nd Erfurt-Windischholzhausen , Weimar (Großer Ettersberg) , Jena (Kernberge) , Inselsberg

1) To receiveARD-alpha HD (Internet)andSWR BW HD (Internet), anhbb-TV capabledevice is required.

Digital television ( DVB-T )

The DVB-T broadcasts from Mitteldeutscher Rundfunk on the Großer Inselsberg had been running since July 1, 2008 and were discontinued on November 28, 2018 when the DVB-T2HD process was switched to.

channel Frequency  
(MHz)
Multiplex Programs in multiplex ERP  
(kW)
Antenna pattern
round (ND) /
directional (D)
Polarization
horizontal (H) /
vertical (V)
Modulation
method
FEC Guard
interval
Bit rate  
(Mbit / s)
SFN
53 730 ARD Digital (MDR) 50 ND V 64-QAM 
2/3 1/4 19.91 -
48 690 ARD regional (MDR Thuringia) 50 ND V 64-QAM  2/3 1/4 19.91 -
50 706 ZDFmobil 50 ND V 16 QAM 
(8 k mode)
2/3 1/4 13.27 -

Analog television

Until the switch to DVB-T , the following programs were broadcast in analogue PAL :

channel Frequency  
(MHz)
program ERP
(kW)
Transmission diagram
round (ND) /
directional (D)
Polarization
horizontal (H) /
vertical (V)
5 175.25 The First (MDR) 100 ND H
31 551.25 MDR television (Thuringia) 500 ND H

In addition, the commissioning of channel 48 with an effective radiated power of 1 megawatt was planned for a private broadcaster, but this was never carried out.

Similar towers in this series

Individual evidence

  1. Manfred Bocklitz: 50 years of radio transmitter station Großer Inselsberg . In: Hörselbergbote . Issue 53. Reissig, Wutha-Farnroda 2003, p. 30-37 .
  2. a b c Manfred Bocklitz: 50 years of radio transmitter station Großer Inselsberg . In: Hörselbergbote . Issue 53. Reissig, Wutha-Farnroda 2003, p. 31 .
  3. In this "pioneering time" of the station, the broadcast technicians and engineers had to cope with conditions that are unimaginable today, so there were no official apartments on the mountain, shift work and the way to and from work turned out to be an adventure in wintry weather.
  4. a b Manfred Bocklitz: 50 years of radio transmitter station Großer Inselsberg . In: Hörselbergbote . Issue 53. Reissig, Wutha-Farnroda 2003, p. 35 .

Web links

Commons : Sender Inselsberg  - Collection of images, videos and audio files