| 摘要 |
A digital control type volume control circuit is disclosed herein which includes a multivibrator, an UP key, a DOWN key, a pair of binary UP/DOWN counters, a 4-to-16 line decoder, an encoder and an attenuator. The multivibrator is connected to the UP and DOWN keys to furnish pulses to the counter via an actuated one of the UP and DOWN keys. The counter counts the number of the pulses via the UP and DOWN key, with the counter being indicative of the length of actuation of the UP or DOWN key. The encoder responsive to the count of the counter output count provides an output for the attenuator having a plurality of resistors of different resistances for determination as to the amount of attenuation.
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