| 摘要 |
<p>The signal level monitor, for data telecommunications systems, releases indicating signal according to whether the input signal exceeds a reference level. The indicating signal is the output signal of an integrator (13) to which a composite DC voltage is supplied. This composite voltage consists of two separately rectified DC voltages one of which is proportional to the required reference level. The second DC voltage is held in a memory (17, 18) circuit containing an FET switch (16) operated by the integrator output. The integrator output is passed over a timing circuit (22) that opens the switch for a time when the output vinishes.</p> |
