| 摘要 |
The control device comprises a small circuit or module which can be fitted in an existing receiver or may be installed during receiver assembly. It consists of one or more adjustable op-amp voltage comparators controlled by the AGC regulation voltage of the high or medium frequency amplifiers in the TV receiver. - The voltage comparator measures the AGC voltage (A) by opposition to a reference voltage obtained from a potentiometric dividing chain and an electroluminescent diode which lights up when the AGC voltage to be measured passes the reference voltage. Pref. the control device has four comparator circuits, each with an LED (D1,D2,D3,D4) and a potentiometer (P1,P2,P3,P4), a resistance (R1) and a Zener diode. The four LEDs measure different levels of AGC voltage corresp. to different input levels.(1/1)
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