| 摘要 |
PURPOSE:To enable to perform the reliable visual observation of level position of a bar, by a method wherein, in the bar displayed on the screen of a picture tube, a level line, which is different in a color from the other part, is displayed in a given level part. CONSTITUTION:An audio signal reaching an input terminal 1 is supplied to a multiplexer 4 via octave-filters 21-210 and an attenuator 3, and a spectrum signal is time-divided in turn and fetched for the duration of a horizontal scanning period. The spectrum signal is compared with a comparing voltage, in which a voltage level changes with the passage of a time for the duration of the vertical scanning period of a picture signal, at the inside of a comparator 14, and the comparing voltage is supplied to a picture tube 11 via a blanking circuit 15 and a RF modulator 17. Meanwhile, a color selecting circuit 22 supplies a pulse signal of an H-level to a video display generator 5 for the duration of a vertical scanning period corresponding to a region displaying Odb or more, the level is displayed in red as a bar, and a level of less than Odb is displayed in green as a bar. |
