wttw chicago productions wttwn national productions channels digital 47 uhf virtual 11 psip subchannels 11.1 pbs 11.2 wttw prime 11.3 create world 11.4 v me affiliations pbs american public television owner window to the world communications inc. first air date september 6 1955 ; 61 years ago 1955 09 06 call letters meaning window to the world sister station s radio wfmt former callsigns digital wttw dt 2000s 2009 former channel number s analog 11 vhf 1955 2009 former affiliations net 1955 1970 transmitter power 300 kw height 465 m facility id 10802 transmitter coordinates 41 52 44 n 87 38 10 w 41.87889 n 87.63611 w 41.87889 ; 87.63611 licensing authority fcc public license information profile cdbs website www.wttw.com wttw virtual channel 11 uhf digital channel 47 is a pbs member television station and the primary pbs member station located in chicago illinois united states . the station is owned by not for profit broadcasting entity window to the world communications inc. and is sister to classical music radio station wfmt 98.7 fm . the two stations share studio facilities located at the ren e crown public media center on north saint louis avenue adjacent to northeastern illinois university in the city s north park neighborhood ; wttw maintains transmitter facilities located atop the willis tower on south wacker drive in the chicago loop . it also owns and operates the chicago production center a video production and editing facility that is operated alongside the two stations . serving as the local flagship outlet for the service it is one of three pbs member stations in the chicago market alongside wycc channel 20 and gary indiana licensed wyin channel 56 . wttw along with wisconsin public television flagship station wha tv in madison wisconsin serve as default pbs member stations for rockford as that market does not have a pbs station of its own ; both stations are available in that market on local cable providers . contents 1 history 2 technical achievements 3 digital television 3.1 digital channels 3.1.1 wttw dt2 3.2 analog to digital conversion 4 programming 5 references 6 external links history edit wttw first signed on the air on september 6 1955 as a member station of national educational television net . the station was founded by a group of civic minded chicagoans led by inland steel executive edward r. ryerson . channel 11 came to life during the first year of the inaugural term of mayor richard j. daley ; daley ryerson and businessman irving b. harris were responsible for creating wttw which began its life as an exhibit at the museum of science and industry in chicago s jackson park . the wttw call letters were chosen as the founders wanted the station to be chicago s window to the world . the station s transmitter was given to wttw by the staff and management of the defunct ks2xbs a pay television station on vhf channel 2 that was forced to shut down as a result of cbs owned and operated station wbbm tv s relocation to that channel in july 1953 . ryerson recruited a young communications lawyer newton n. minow to join the station s board ; minow would both serve as chairman of the wttw board and as commissioner of the federal communications commission fcc under the administration of president john f. kennedy . irving b. harris henry w. brick meers john w. mccarter jr. martin j. mike koldyke and sandra p. guthman have served as chairman of the board for the public broadcaster in subsequent decades . guthman a member of the famous polk brothers family of chicago is the current chairman of the board having served in that post since october 2003 . birgit ridderstedt with son lars left of her and other children after their appearance on the totem club program in 1959 . minow stated that the only really important decision that he made during his tenure as chair of wttw was the recruitment of william j. mccarter jr. as president and chief executive officer a post which he held for 27 years . having run public station weta tv in washington d.c. mccarter a decorated korean war hero and a veteran television pioneer got his start in the broadcasting industry as a cameraman for american bandstand and then as a part of the army mccarthy hearings on capitol hill . mccarter developed the concept of the political roundtable that is now a staple of television news . in non commercial television circles mccarter is referred to as the architect of public television his friends know him as the man who kicked bob dylan who was set to tape an episode of soundstage and was found by mccarter asleep on the couch in the room out of his office waking the bearded dylan up and ushering him out of the office after mccarter returned from a meeting . during the 1960s wttw aired educational programming during the daytime hours showing programs produced under the auspices of chicago area schools television cast . programs from tv college covering college subjects were also shown on weekdays . other afternoon shows included a locally produced series titled the storyteller which featured a children s story presented weekdays at 5 30 p.m. and was sponsored by the locally based marshall field & company department store chain . on october 5 1970 wttw became a charter member station of the public broadcasting service pbs . wttw did not broadcast programming on saturdays until the summer of 1972 when it began airing a limited schedule of programming on that day until 2 00 p.m. ; the station expanded its saturday programming scheduled to a full broadcast day in 1974 . in the late 1970s and early 1980s wttw was used during the overnight hours as a test vehicle in the development of stereophonic sound for television audio broadcasts . in 1981 the chicago educational television association founded chicago magazine as the program guide for wttw and wfmt ; the publication was sold to a joint venture between metropolitan detroit magazine and adams communications in 1986 for 17 million . 1 on november 22 1987 wttw s signal was hijacked by an unknown person wearing a max headroom mask the second such signal interruption incident to occur in the chicago area that night with the first taking place during the 9 00 p.m. newscast on independent station wgn tv channel 9 s two hours prior to the hacker s intrusion of the wttw signal . while wgn tv s analog transmitter was located atop the john hancock center at the time allowing for engineers to almost immediately thwart the video hacker by changing the studio to transmitter frequency wttw s transmitter was located atop the sears tower now the willis tower which made it harder to stop the hacker before the interruption voluntarily concluded after almost two minutes . 2 3 on june 4 2010 window to the world communications announced that it would lay off around 12 % of wttw and wfmt s employee base and extend a salary freeze instituted in 2009 for one additional year in an effort to cut 3 million in operating costs due to declining revenue effects from the economic downtown and the loss of 1.25 million in grant money from the illinois general assembly . 4 on april 15 2014 window to the world communications renamed the broadcasting facilities for wttw and wfmt fm as the ren e crown public media center following a monetary gift of an undisclosed amount by the family of ren e crown who has served as a trustee for window to the world since 1981 . 5 6 technical achievements edit wttw has long been a pioneer in many technical aspects of television broadcasting particularly in broadcast audio transmission . the station in particular participated in the trend of pop music focused programs on television during the early 1970s a few of which were also simulcast on local fm radio stations . when wttw began production on made in chicago the station made the decision to transition from monoaural audio to stereo for the fm broadcasts . however stereo recording equipment for television production did not exist at that time . because of this wttw engineers chose to modify existing ampex quadruplex recorders to provide a stereo medium in sync with the video portion of the program . this innovation earned the station s staff a local technical emmy award in 1973 . further refinements to this system resulted in improvements to both frequency response and noise reduction and eventually led to the ability to edit stereo audio as the video was being edited electronically . dolby laboratories noise reduction technology type c and then type a was introduced as the staff was driven to make improvements in the audio specifications . wttw began syndicating made in chicago to other public television stations under the new title soundstage with the first official taping of that program in june 1974 featuring jim croce . the station was broadcast in simulcast fm stereo with wxrt 93.1 fm and wbbm fm 96.3 as participating stations in the manner of its predecessor . in 1975 wttw management was approached by a startup company called telesonics with an idea to develop an audio system for television broadcasts that used a mono compatible stereo audio channel . around this time the sears tower had been completed and wttw became one of the first broadcasters to move its transmitter facilities atop the new building ; wttw had broadcast from a temporary antenna as the now familiar twin towers that adorn the top of the building had not yet been completed . 7 digital television edit digital channels edit the station s digital channel is multiplexed channel video aspect psip short name programming 8 11.1 720p 16 9 wttw hd main wttw programming pbs 11.2 480i prime wttw prime 11.3 cr wo create world 11.4 4 3 v me v me wttw also plans to operate a mobile dtv feed of subchannel 11.1 which will broadcast at 1.83 mbit s. 9 10 wttw s main channel and all of its subchannels are available on comcast systems in the market . in may 2015 wttw downgraded the resolution of its main channel from 1080i to 720p which the station had previously transmitted its high definition content in prior to september 2009 during which time it downconverted hd content provided by pbs from their native 1080i format . wttw dt2 edit from the sign on of its digital signal in 2004 until 2009 wttw branded its main digital channel on 11.1 as wttw digital featuring a full schedule of programs available in high definition while digital subchannel 11.2 rebroadcast the main programming schedule of analog channel 11 . in september 2008 digital channel 11.1 was converted into a simulcast of the analog signal s programming resulting in it carrying the same programing schedule as 11.2 . on march 30 2009 11.2 was relaunched with a separate schedule as wttw prime which features a mix of pbs primetime programs and wttw s locally produced programming particularly during the period from 6 00 a.m. to 6 00 p.m. when children s programming airs on the main channel . wttw prime carries some pbs programs in their traditional timeslots most notably a block of the service s public affairs programs that run on friday evenings and a weekdaily airing of the nightly business report at 5 30 p.m. wttw prime is also available on comcast digital channel 370 . 11 12 analog to digital conversion edit wttw shut down its analog signal over vhf channel 11 on june 12 2009 the official date in which full power television stations in the united states transitioned from analog to digital broadcasts under federal mandate . the station s digital signal remained on its pre transition uhf channel 47 . 13 through the use of psip digital