PURPOSE: To prevent the deterioration in sound quality at AM receiving, by controlling a deemphasis circuit in response to a switching means for switching a power supply voltage to both AM and FM receivers.
CONSTITUTION: A changeover switch 10 switches the voltage of a DC power supply 9 to a front end circuit 3, an IF circuit 4, and an FM detecting circuit 5 of the AM receiver 8 and the FM receiver 2, and a control circuit 11 performs on/off control of the deemphasis circuit 7. In switching the switch 10 to the AM position, the power supply voltage is applied, the circuit 7 is turned off, the high-frequency component of the detected output at the time of AM receiving is attenuated at the circuit 7, thereby preventing the deterioration in sound quality.
| JP2010200294 | DIGITAL DATA PROCESSING CIRCUIT |
TAJIMA HIROSHI
ITOU HIDEO
| JPS5623050A | 1981-03-04 | |||
| JP52116110B | ||||
| JP55074152B |