long wave station, 5XX in Daventry, Northamptonshire, participated in the first British stereo broadcast a concert from Manchester, conducted by Sir Hamilton Harty with 5XX transmitting nationally the right channel, and local BBC stations broadcasting the left channel on mediumwave. The BBC repeated the experiment in 1926, using 2LO in London and 5XX at Daventry. On June 12, 1946 a similar experimental broadcast using two stations was conducted in Holland, which was mistakenly thought to be the first in Europe and possibly the world. 1952 saw a renewed interest in the United States in stereo broadcasting, still using two stations for the two channels, in part in reaction to the development of two-channel tape recordings. The Federal Communications Commission's (FCC) "duopoly" rule limited station owners to one AM station per market. But many station owners now had access to a co-owned FM station, and most of these tests paired AM and FM stations. On May 18 KOMO and KOMO-FM in Seattle, Washington conducted an experimental broadcast, and four days later Chicago AM radio station WGN and its sister FM station, WGNB, collaborated on an hourlong stereophonic demonstration. On October 23, 1952 two Washington, D.C. FM stations, WGMS-FM and WASH, conducted their own demonstration. Later that month New York City's WQXR, paired with WQXR-FM, initiated its first stereophonic broadcast, which was relayed to WDRC (Franklin Doolittle's former WPAJ, now located in Hartford, Connecticut) and WDRC-FM."WDRC" (advertisement), Broadcasting, December 8, 1952, page 9. By 1954, WQXR was broadcasting all of its live musical programs in stereophonic sound, using its AM and FM stations for the two audio channels. Rensselaer Polytechnic Institute began a weekly series of live stereophonic broadcasts in November 1952 using two AM stations, WHAZ in conjunction with a very low powered local carrier current station, which meant the stereo listening area did not extend beyond the college campus. The revived dual transmitter tests were of limited success, because they still required two receivers, and with AM-FM pairings the sound quality of the AM transmissions were generally significantly inferior to the FM signals. FM standards The Zenith-GE pilot-tone stereo system is used throughout the world by FM broadcasting stations. It was eventually determined that the bandwidth assigned to individual FM stations was sufficient to support stereo transmissions from a single transmitter. In the United States the FCC oversaw comparison tests, conducted by the National Stereophonic Radio Committee, of six proposed