| 摘要 |
PURPOSE:To obtain a signal generator for accurate signal intensity display, through a DC level output proportional to the logarithms of an input level with a wide dynamic range and high accuracy, by providing a gain control type amplifying means and controlling this output level so as to be at a prescribed range at all times. CONSTITUTION:A gain controlling type amplifier means 10 to which an input signal IN to be displayed of signal intensity and the gain of which is stepwise changed with external control signals A-D, is provided, this output is detected at an AM detection circuit 20 to obtain a DC level, a window comparator 30 detects that the detection level is at the outside of a prescribed range, the signals A-D are changed, the output level is always controlled to be within this range, and the control signals A-D, window comparator outputs E, F and a detected output are applied to an illuminating signal generating circuit 50 to control LED displays 15 arranged in a line. |
