Transmitting systems on the Großer Feldberg

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Transmitting systems on the
Großer Feldberg
Radio transmission point Königstein 1
Image of the object
Transmitting systems (from left to right): HR pipe mast, Volume III VHF replacement mast, observation tower with VHF replacement antennas, telecommunications tower of Deutsche Funkturm GmbH (since March 2007 without antenna)
Basic data
Place: Great Feldberg
Country: Hesse
Country: Germany
Altitude : 879  m above sea level NHN
Coordinates: 50 ° 13 ′ 55.9 ″  N , 8 ° 27 ′ 31.7 ″  E
Use: Telecommunication system , radio transmitter
Accessibility: Transmission system not accessible to the public
Owner : Hessischer Rundfunk , German radio tower
Data on the transmission system
Tower / mast 1
Construction time: 1937
Operating time: since 1937


Tower / mast 2
Construction time: 1949
Operating time: since 1949
Last modification (transmitter) : October 2004
Waveband : FM transmitter
Radio : VHF broadcasting
Send types: Directional radio , amateur radio service
Position map
Transmitting systems on the Großer Feldberg (Hesse)
Transmitting systems on the Großer Feldberg
Transmitting systems on the
Großer Feldberg
Localization of Hessen in Germany

On the Großer Feldberg im Taunus ( Hochtaunus ) - near Ober- and Niederreifenberg in the municipality of Schmitten in the Hessian Hochtaunuskreis  - there are several transmission systems for television, radio and amateur radio .

Telecommunications tower

From left to right: telecommunication tower, hr tube mast and observation tower, on the far right the Feldberghof

In 1937, a telecommunications tower made of reinforced concrete and a wooden structure was built on the Großer Feldberg ( 879  m above sea  level ) , which was originally intended to serve as a television transmission tower and was used for military purposes during the Second World War . In 1945 the tower was almost completely destroyed after being hit by bombs. The reconstruction took place in 1950/51 in a different form. Because of its unique construction, it has been a listed building since 1987 . The antenna of the former VHF radio and UHF TV transmission system on the Großer Feldberg telecommunications tower was dismantled in 2007.

The Deutsche Funkturm (DFMG), a subsidiary of Deutsche Telekom , is the owner of the tower and is operated by T-Systems , also a subsidiary of Deutsche Telekom.

Here, until the switch to DAB-T / DVB-T Hit Radio FFH (105.9  MHz with 100  kW ) and AFN (98.7 MHz with 60 kW) were broadcast horizontally and ZDF ( Channel  34 with 500 kW) and hr television (channel 54 with 500 kW) also broadcast horizontally as omnidirectional.

Observation tower

Lookout tower on the Großer Feldberg, to the left of it the radio mast of the hr

The observation tower , built in 1902 by the Taunus Club , was rammed by a German military aircraft in the thick fog in 1943 and burned out completely. In 1949 the Hessischer Rundfunk rebuilt the tower with the antenna carrier for the VHF frequency on its top. The antenna carrier is now a reserve system.

hr tubular mast

The tallest structure on the Großer Feldberg is a 116.17 m high, guyed tubular mast of the Hessian Radio for broadcasting radio and television programs.

When T-Systems was still operating the transmission system on the telecommunication tower, the high-speed FM programs and Das Erste (Channel 08 with 100 kW in omnidirectional radiation and horizontal polarization ) were broadcast from the high-speed tubular mast.

On October 4, 2004, DVB-T broadcasts began here together with two other locations in the Rhine-Main area. Since the DVB-T conversion in the remaining parts of Hesse on May 29, 2006, all radio services, be it television or radio, have been broadcast from the hr pipe mast. Due to the higher antenna position, the effective radiated power of AFN has been reduced from 60 kW to 50 kW horizontal omnidirectional radiation.

On January 18, 2017, AFN handed over the 98.7 MHz frequency, on which the numerous American military bases in the Rhine-Main area and in the Gießen / Wetzlar area had been supplied for over 50 years, to Deutschlandfunk . This is the first time that it can be received nationwide in the region on VHF. Since then, AFN can only be heard in Wiesbaden via the Mainz-Kastel transmitter for the nearby military installations.

hr building

HR building (left) next to observation tower (right) 2015

The Hessischer Rundfunk building with the broadcasting hall and switch room is located between the hr tube mast and the observation tower. The building has a reserve mast.

Frequencies and Programs

Analog radio (FM)

The first VHF radio program in the Rhine-Main area started here. In 1952 the HR Frankfurt or First Program was broadcast on 89.3 MHz with 10 kW ERP . Another program, then called the Second Program (today's hr2-kultur ), also ran with 10 kW ERP at 93.3 MHz. In 1954 the first program broadcast with 60 kW ERP on 88.5 MHz, the second program then ran on 92.1 MHz, also with 60 kW ERP. Back then, all frequencies ran in horizontal omnidirectional radiation, just like today.

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)
94.4 hr1 __hr1___  1) D361 - 100 ND H
96.7 hr2 culture __hr2___  1) D362 - 100 ND H
89.3 hr3 __hr3___  1) D363 - 100 ND H
102.5 hr4 hr4_Sued,
__hr4___  1) 		D864 (regional), 
D364 		Rhine-Main 100 ND H
105.9 Hit Radio FFH __FFH-F_,
HITRADIO / ___ FFH__  1) 2) 		D668 (regional), 
D368 		Rhine-Main 100 ND H
98.7 Deutschlandfunk __Dlf___ D210 - 60 ND H
1) Sometimes dynamic with program information, music track information or web addresses
2) Dynamic, partly with news

Digital radio (DAB)

DAB or Digital Mobile TV (DMB) is in vertical polarization and the simulcast broadcast single frequency network () with other stations. DAB from Hessen Digital Radio in Band III VHF started here on January 1, 2001 and was only broadcast from here until November 1, 2001.

block Programs ERP  
(kW) 		Antenna pattern
round (ND) / directional (D) 		Single frequency network (SFN)
5C 
Germany 
(D__00188) 		DAB + multiplex from Media Broadcast : 5 D (60 °)
7B 
hr radio 
(D__30122) 		DAB + multiplex of the HR :
  • hr1 (136 kbps)
  • hr2 (144 kbps)
  • hr3 (136 kbps)
  • hr4 Rhine-Main (south) (136 kbps)
  • hr4 north / east (north) (136 kbps)
  • hr4 central Hesse (center) (136 kbps)
  • YOU FM (136 kbps)
  • hr-iNFO (88 kbps)
  • hr EPG (32 kbps)
  • hr journaline (32 kbps)
  • hr TPEG (32 kbps)
5 D (60 °)
12C 
DR Hessen 
(D__00207) 		DAB multiplex from Hessen Digital Radio: 4.5 D (80 °) Großer Feldberg (Taunus) , Frankfurt (Europaturm) , Hardberg (Odenwald) , Mainz-Kastel


The mobile phone TV operator MFD returned the licenses for DMB in 2008. All projects in Germany relating to this standard were terminated by 2010. For the transmission of mobile phone TV, DVB-H , which was endorsed by the EU Commission , initially prevailed.

Digital television

DVB-T

The DVB-T broadcasts from the tube mast of the Hessischer Rundfunk run in single-frequency operation with other broadcasting locations. This network was the first of its kind in the whole of Hesse when it gradually started on October 4 and December 6, 2004. It was stopped on March 29, 2017.

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
22nd 482 ZDFmobil 50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel, Rimberg ( Knüll )
34 578 RTL Group Hessen 50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel
37 602 ARD Digital (hr) 50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg ( Taunus ) , Europaturm ( Frankfurt ), telecommunications tower Hohe Wurzel (Taunus near Wiesbaden ), Würzberg ( Odenwald )
39 618 ARD regional (hr) Rhein-Main 50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel
52 722 Mixed private Rhein-Main 
( Media Broadcast , BetaDigital 
[Tele 5])

HbbTV services

50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel
54 738 ProSiebenSat.1 Media Hessen 50 ND V 16 QAM 
(8 k mode) 		2/3 1/4 13,271 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel
59 778 DVB-T2 HD
media broadcast , freenet TV
 50 ND V 64 QAM 
(32 k mode) 		2/3 1/16 27.620 Großer Feldberg , Europaturm, telecommunications tower Hohe Wurzel

DVB-T2 HD

On May 31, 2016, the broadcast of the high definition DVB-T2 HD in the Rhine-Main area began. Since then, Das Erste, ProSieben , Sat.1 , RTL , VOX and ZDF can be received via antenna on channel 59 with 50 kW from Feldberg in High Definition (HD). The Europaturm in Frankfurt am Main and the telecommunications tower Hohe Wurzel in Wiesbaden also broadcast the HD signal on channel 59. Regular operation of DVB-T2 started on March 29, 2017.

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
22nd 482 ZDFmobil 50 ND V 64-QAM
( 16k  mode) 		3/5 19/128 22nd Großer Feldberg ( Taunus ) , Europaturm ( Frankfurt ), Hohe Wurzel (Taunus near Wiesbaden ), Darmstadt-Weiterstadt Darmbach, Rimberg ( Knüll )
25th 506 ProSiebenSat.1 Media
Media Broadcast , freenet TV
 50 ND V 64 QAM 
(32 k mode) 		2/3 1/16 27.60 Großer Feldberg , Europaturm, Hohe Wurzel, Darmstadt-Weiterstadt Darmbach
31 554 RTL Group
Media Broadcast , freenet TV
 50 ND V 64 QAM 
(32 k mode) 		2/3 1/16 27.60 Großer Feldberg , Europaturm, Hohe Wurzel, Darmstadt-Weiterstadt Darmbach
34 578 ARD regional (hr) Rhein-Main 50 ND V 64-QAM
( 16k  mode) 		3/5 19/128 22nd Großer Feldberg , Europaturm, Hohe Wurzel, Darmstadt-Weiterstadt Darmbach, Würzberg ( Odenwald )
42 642 ARD Digital (hr) 50 ND V 64-QAM
( 16k  mode) 		1/2 19/128 18.34 Großer Feldberg , Europaturm, Hohe Wurzel, Darmstadt-Weiterstadt Darmbach, Rimberg
47 682 Mixed private Rhein-Main 
Media Broadcast , freenet TV
 50 ND V 64 QAM 
(32 k mode) 		2/3 1/16 27.60 Großer Feldberg , Europaturm, Hohe Wurzel, Darmstadt-Weiterstadt Darmbach

Amateur radio

Amateur radio relays are housed in the old telecommunications tower of the DFMG and in the observation tower of the hr . The relays are often called “2 m Feldberg” or “70 cm Feldberg” among radio amateurs . The amateur radio relay is operated by the Taunus Relais Group . It reports current faults and provides detailed information on the system on the Großer Feldberg on its website.

Relay type Callsign tape Others
FM relay DB0FT 2 m + 70 cm Location: DFMG, VHF relay with 2 receivers, UHF relay / multimode relay
FM relay DB0HRF 70 cm Location: observation tower
FM shortwave relay DF0MOT 10 m Location: observation tower, receiver on Kl. Feldberg (DB0MOT)
Paging transmitter POCSAG DB0HRF 70 cm Location: observation tower
Packet radio digipeater DB0HRF 70 cm / 23 cm Location: observation tower
Digital relay DB0HRF 70 cm Location: observation tower, D-STAR Digital Voice
Digital relay DB0HRF 23 cm Location: observation tower, D-STAR Digital Voice
Digital relay DB0HRF 23 cm Location: observation tower, D-STAR Digital Data
Digital relay DF0MOT 70 cm Location: observation tower, APCO-P25 standard
Digital relay DF0MOT 70 cm Location: observation tower, DMR standard, DMR + network
Digital relay DF0MOT 70 cm Location: observation tower, DMR standard, fire supervisor network
Digital relay DB0HRF 70 cm Location: Observation tower, Yaesu system fusion (Continuous 4 level FM)

Changes in recent years

Analog radio

The military radio service AFRTS (Armed Forces Radio and Television Service), to which AFN TV and AFN Radio belong, introduced the identifier 98.7 ___ on May 10, 2004, after no RDS PS had been activated so far . On May 29, 2006, all VHF radio programs that had previously been broadcast from the telecommunications tower were relocated to the hr tube mast. At the beginning of April 2008, AFRTS changed the RDS-PS identifier to AFNEAGLE .

Frequency  
(MHz) 		program ERP at the DTAG telecommunications tower  
(kW) 		ERP on the hr tubular mast  
(kW)
105.9 Hit Radio FFH 100 100
98.7 AFN The Eagle Hessen / Z-98 60 50

The other parameters correspond to the VHF table , with the AFN frequency being transferred to Deutschlandfunk in January 2017.

Analog television

Before DVB-T started , the following programs ran in analogue PAL on the Großer Feldberg until December 6, 2004 .

channel Frequency  
(MHz) 		program ERP  
(kW) 		Antenna pattern
round (ND) /
directional (D) 		Polarization
horizontal (H) /
vertical (V) 		Transmission mast
8th 196.25 The first (hr) 100 ND H hr tubular mast
34 575.25 ZDF 500 ND H DTAG telecommunications tower
54 735.25 hr television 500 ND H DTAG telecommunications tower

Digital television

The DVB-T transmission antennas are only mounted on the hr tube mast on the Großer Feldberg.

At the start of DVB-T in Rhine-Main on October 4, 2004, changes were made to the channel distribution. Channel 57 in Aschaffenburg Gailbach ( Stengerts ) with ProSieben (then 200  W horizontal omnidirectional radiation) was discontinued. Channel 22 in Wiesbaden with AFN Prime Atlantic (Hessen) was relocated to channel 42 and ran unchanged with 2 kW horizontal omnidirectional radiation until the beginning of June 2008. On October 4, 2004, Kanal 22 ( ZDFmobil Multiplex : ZDF, ZDFinfo with 3sat , KiKA with ZDFneo and the now discontinued MHP service ZDFdigitext ) and Kanal 57 ( ARD Digital national / regional multiplex: Das Erste (hr), the former Hessen Fernsehen , the then Südwest Fernsehen RP and Phoenix ) are already going digital . The other channels (8: Das Erste (hr), 34: ZDF and 54: Hessen Fernsehen) continued to run analogue until December 6, 2004. On that day, Kanal 64 (mixed private Rhein-Main Multiplex: rheinmaintv , Eurosport and the now discontinued terranova and tvnah ) was added. In Rhein-Main, vertical polarization has been chosen for the transmission of DVB-T in order to facilitate indoor antenna reception .

On May 29, 2006, in the course of the introduction of DVB-T in other areas of Hesse, some changes were made to the channel occupancy and the technical parameters of the transmitters in Rhine-Main. For example, the multiplex ARD Digital national (hr) was moved from channel 8 to channel 57, as Band III VHF reception in indoor antenna areas is very difficult with the antennas often included with DVB-T receivers . These antennas are mostly only suitable for UHF band IV / V reception. For this reason and because of the plan to sporadically switch on Dolby Digital content behind its main programs Das Erste (hr) and HR television, which require more bit rates, the HR decided to multiplex these programs on a Band IV / V UHF channel and adjust the parameters of Band III VHF channel 8 in favor of more stable reception behavior by changing the error protection from 3/4 to 2/3. This adjustment leads to a lower total bit rate of channel 8, which offered a bit rate of 13.06 Mbit / s until May 29, 2006  and today only offers 11.61 Mbit / s. That is why the broadcasting of WDR television has been dispensed with in favor of better picture quality in the other programs. At the same time, the full broadcast of the EinsFestival program , which previously occupied its own program slot, has been discontinued throughout Hesse . Now arte shares a program space with EinsFestival (now renamed one). The HR uses the freed-up capacity for the aforementioned Dolby Digital transmissions. Likewise, the saving of a program space should in turn lead to better picture quality for the other programs in the multiplex of channel 57.

On December 4, 2007, the multiplex ARD Digital national (hr) was moved from channel 57 to channel 37. This channel was previously in operation on Donnersberg ( Kirchheimbolanden ) in the Palatinate and for decades it broadcast the ZDF program analogously. The multiplex ARD Digital national ( SWR ) is now running on channel 57 on the Donnersberg.

At the beginning of June 2008 a DVB-H test of Mobile 3.0 started on channel 42 from the Europaturm in Frankfurt. As a result, AFN Prime Atlantic Hessen from Wiesbaden was moved from channel 42 (2 kW ND H ) to channel 29 and now only runs with 1 kW horizontal omnidirectional radiation. Due to a better frequency situation, in some cases even better reception of AFN was possible than before.

On July 15, 2008, the analog terrestrial broadcast of AFN Prime Atlantic Hessen was discontinued in all of Hessen. Channel 29 in Wiesbaden has been out of service since then.

The DVB-H test run ended in November 2008.

After a long time, on November 7, 2008 , a fourth program was switched on again in the mixed private multiplex Rhein-Main on Kanal 64 with Bibel TV .

On November 25, 2008, in the course of the activation of DVB-T at Pfaffenberg near Aschaffenburg, the regional version North (Franconia) on Bavarian TV for DVB-T in the Rhine-Main area was activated. Before that, the version south (Swabia / Old Bavaria) was activated.

On October 27, 2010, the mixed private multiplex Rhein-Main switched from channel 64 to channel 52. Since the frequency auction 2010 for LTE , the area over channel 60 has been reserved for other services.

Future changes

Following the coordination and agreement of the Regional Radiocommunication Conference 2006 (RRC 06), channels that can be used for Hessen in the future have been defined internationally. The decision-making authority at national level with regard to the allocation of channels to the program providers rests with the Federal Network Agency (BNetzA), which could theoretically also determine a different distribution of the available channels.

In DAB, a Band III VHF channel is divided into four parts, also known as four blocks or, in the case of frequency coordination, also called four layers. With DVB-T, a band IV / V UHF channel (in exceptional cases also a band III VHF channel) is equal to a multiplex or bouquet . Here the channel is referred to as a layer in the frequency coordination.

The coordination according to RRC-06 is listed below. The entries relating to the Großer Feldberg are highlighted.

DAB

block Layer Coverage area
12C (in operation) VHF layer 1 Hesse
11C VHF layer 2 Hesse
06A VHF layer 3 South Hesse
06C VHF layer 3 North Hesse
06D VHF layer 3 Central Hesse

DAB / DVB-T

block Layer Coverage area
07A VHF layer 4 Hesse
07B VHF layer 4 Hesse
07C VHF layer 4 Hesse
07D VHF layer 4 Hesse

DVB-H

The DVB-H standard was created for mobile devices with a small display and offered a very robust signal. Some of the services that should be transmitted here should be freely available, and some should be subscribed to for a fee. The operation did not get beyond a test phase. It was planned that DVB-H would ideally be broadcast like DVB-T from several locations in single-frequency operation. According to planning by the Hessian State Authority for Private Broadcasting and New Media (LPR Hessen), regular DVB-H operation was planned in Hesse in the following coverage areas - also known as coverage areas. Tests under the Mobile 3.0 (MFD) joint venture ended on November 2, 2008 and the licenses were then returned. A large-scale restart of the system under a new operator consortium was not implemented.

channel Layer Coverage area
28 UHF layer 4 North Hesse
47 UHF layer 6 Central Hesse
42 UHF layer 6 Rhine-Main , South Hesse

DVB-T

The following RRC-06 assignments are already in operation in Hesse (sorted according to the respective multiplex).

channel Layer Multiplex SFN
32 UHF layer 5 ARD Digital (hr) Essigberg , Hoher Meißner , Rimberg , Angelburg
37 UHF layer 5 ARD Digital (hr) Großer Feldberg , Europaturm , Hohe Wurzel , Würzberg
55 UHF layer 2 ARD regional (hr) North Hesse Essigberg, Hoher Meissner
39 UHF layer 2 ARD regional (hr) Rhein-Main Großer Feldberg , Europaturm, Hohe Wurzel
35 UHF layer 3 ARD regional (hr) East Hesse Rimberg, Heidelstein (assigned to North Hesse)
24 UHF layer 2 ARD regional (hr) Central Hesse Fishing castle
42 UHF layer 1 ZDFmobil Essigberg, Hoher Meissner
22nd UHF layer 1 ZDFmobil Großer Feldberg , Europaturm, Hohe Wurzel, Rimberg
21st UHF layer 1 ZDFmobil Wurzberg, Königstuhl
54 UHF layer 2 ProSiebenSat.1 Hessen Großer Feldberg , Europaturm, Hohe Wurzel
34 UHF layer 4 RTL Group Hessen Großer Feldberg , Europaturm, Hohe Wurzel

The assignments in the following table are still available.

channel Layer Coverage area
52 UHF layer 6 North Hesse
58 UHF layer 4 Central Hesse
59 UHF layer 3 Rhine-Main , South Hesse
61 UHF layer 7 Nordhessen, Mittelhessen Reserved
for LTE since the frequency auction 2010 , see digital dividend
63 UHF layer 7 Rhein-Main , Südhessen 
(only available from 2015) Reserved
for LTE since the frequency auction 2010 , see digital dividend

The channels below do not correspond to the RRC-06 assignment for the respective area and can move to the assignments that are still free.

channel Multiplex SFN
25th ZDFmobil Heidelstein
45 ZDFmobil Fishing castle
43 ARD Digital (hr) Heidelstein
52 Mixed private Rhine-Main Großer Feldberg , Europaturm, Hohe Wurzel In
operation as a replacement since the clearing of Canal 64 in the Rhine-Main area, possibly permanent occupancy and thus deviation from the plan of the RRC06. This coverage is Layer 2 in Northern Hesse.
53 ARD regional (hr) South Hesse Wurzberg

See also

Web links

Commons : Großer Feldberg communication tower  - collection of images, videos and audio files

Individual evidence

  1. ↑ Hessisches Statistisches Landesamt : Statistisches Jahrbuch 2011/12, Volume 2, Page 21; Retrieved January 5, 2014
  2. ↑ The telecommunications tower on the Großer Feldberg / Ts. In: Bäsembinner Bläädche. wolfenhausen.de, October 25, 2013, accessed on May 26, 2015 .
  3. ↑ Tower without a point. (No longer available online.) In: faz.net. FAZ , March 22, 2007, archived from the original on May 26, 2015 ; accessed on March 28, 2018 .
  4. ↑ Helmut Bode (ed.): The Feldberg book . Waldemar Kramer Verlag, 1992, ISBN 3-7829-0303-X .
  5. ↑ Hesse's highest construction site is on the Großer Feldberg. In: FAZ faz.net, August 19, 2004, accessed on May 26, 2015 .
  6. ↑ Patrick Jütte: US military broadcaster AFN is moving. In: fr-online.de. Frankfurter Rundschau , January 18, 2017, accessed on January 20, 2017 .
  7. ^ The duo of the Feldberg broadcasting station. In: Frankfurter Rundschau. fr-online.de, July 23, 2014, accessed on May 26, 2015 .
  8. ↑ Reception areas of DVB-T2 HD - first stage from May 31, 2016. (PDF) In: dvb-t2hd.de. Project office DVB-T2 HD Germany, June 2016, accessed on January 20, 2017 .
  9. ↑ Relay status of the Taunus relay group. Taunus Relais Group, accessed on March 14, 2017 .
  10. ↑ Roland Brugger, Alexander Schertz, Michael Pausch: The reorganization of the spectrum for digital terrestrial broadcasting: - Results of the Regional Radiocommunications Conference RCC-06 -. (PDF; 1.58 MB) In: teleko.cz. IRT , July 17, 2006, archived from the original on April 11, 2012 ; accessed on May 22, 2016 .