The Cyrillic letter Ka descender or Qaf (in Kazakh) (Қ,қ) is a К with a descender. It is used in a number of Turkic spoken on the territory of the former Soviet Union, including Tajik, Kazakh, Uzbek, Uighur and several smaller languages (Karakalpak, Tofalar), where it represents a voiceless uvular plosive /q/. Since /q/ is represented by the letter ق qaf in the Arabic alphabet, Қ is sometimes referred to as "cyrillic qaf."

Quadrature Active Filter. Qfmax=Qclk/16.