Polyphony and monophony in instruments harpejji and the Chapman stick). Multiphonics can be used with many regular wind instruments to produce two or more notes at once, although this is considered an extended technique. Explicitly polyphonic wind instruments are relatively rare, but do exist. The standard harmonica can easily produce several notes at once. Multichambered ocarinas are manufactured in a number of varieties, including double, triple, and quadruple ocarinas, which use multiple chambers to extend the ocarina's otherwise limited range, but also enable the musician to play more than one note simultaneously. Harmonic ocarinas are specifically designed for polyphony, and in these instruments the range
Owned-and-operated television stations in the United States as WRCA/WRCV did. In 1965, NBC was forced to reverse the trade on orders from the Federal Communications Commission and the United States Department of Justice. WRCV-TV's callsign was then changed to KYW-TV to match its radio cousin. When NBC regained control of the Cleveland stations, it changed their callsigns to WKYC-AM-FM-TV, because of the AM station's popularity as "KY11". It sold the radio stations in 1972, but kept WKYC-TV until 1990, when majority control of the station was sold to Multimedia, Inc. (which later merged with the Gannett Company in 1995); NBC remained minority owner of WKYC-TV until 1999