Kenwood KAC719 free download

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CASSETTE RECEIVER KAC-719 SERVICE MANUAL © 2000-3 PRINTED IN JAPAN B51-7600-00 (S) 3344 Dressing panel (A21-4014-03) Heat sink (F01-1627-01) SUBWOOFER AMPLIFIER FUSE (30A) POWER IN BATT KAC-719 SERVO II P.CON(REMOTE) SPEAKER OUTPUT SERVO II 30 GND Fuse Screw terminal Screw terminal Screw terminal board board (F52-0015-05) board (E70-0820-05) (E70-0818-05) (E70-0808-05) 15Hz OFF 25Hz INFRASONIC 6dB OFF 12dB 150 170 200 1 2 3 4 0.5 0.3 LINE IN L GND 5 0.2 SPEAKER LEVEL INPUT LEFT RIGHT R BASS 100 BOOST 70 50 SUBWOOFER AMPLIFIER LPF FREQUENCY(Hz) INPUT SENSITIVITY(V) Pin jack (E63-0834-05) Screw terminal board (E70-0824-05) Accessory (W01-1515-05) Screw set (N99-1587-05) Accessory (E type only) (W01-0797-05) KAC-719 CIRCUIT DESCRIPTION SP P-CON Switching Circuit When the SP output from the head unit is connected to SP IN, the power can be switched ON/OFF based on the DC voltage of the SP output. However, As certain head unit models output DC permanently or generate a click during switching OFF, it is required to provide the capability of previous P-CON switching. A circuit which can perform the switching without using a switch is described below. This circuit performs switching by inhibiting the operation of the S-P-CON circuit when a voltage is applied to the P-CON pin. Circuit operation description When the head unit is connected to SP-INN, the DC component in the SP output turns Q38 ON through D32 and R158. When a voltage is applied to the P-CON pin under this condition, Q45 is turned ON via R188, positive feedback is applied by combination of Q45 and Q46, Q45 and Q46 are held at ON, so the voltage at point (A) is almost 0 V and the SP-P-CON circuit is not activated. This circuit holds the ON status while the DC voltage from SP is present. Therefore, in this condition, the P-CON circuit continues functioning. To cancel the functioning, the voltage at the SP-IN pin should go 0 V. D29 7.5v to P-CON terminal D32 from SP-P-CON R188 Q46 100k A R158 10u 35 4.7k power control Q38 3.3k ALIGN FOR Q45 ADJUSTMENT No ITEM INPUT SETTINGS OUTPUT SETTINGS TUNER ALIGNMENT (RECEIVER) POINTS SETTINGS FIG. Connect a cassette receiver or other receiver. IDLE CURRENT Connect a DC voltmeter to CN3 After sufficient aging adjust to 2mV 1 ­ Volume : 0 VR3 (a) 2 A B C D E F G H I PC BOARD (Component Side View) AUDIO UNIT X09-5320-10 A/3 (J74-1030-11) INFRASONIC OFF/15Hz/25Hz S1 BASS BOOST OFF/6dB/12dB S2 R39 W56 R47 W38 J2 1 AUDIO UNIT (X09-5320-10) IC3 16 9 W116 E2 R140 C23 R49 R7 R40 C20 R50 R5 R142 R143 R6 VR2 W43 VR1 C3 C7 D38 R23 R22 C10 1 C58 8 W112 R144 Q30 E B B E E Q32 B B C9 R42 R46 W57 W87 W58 R32 R31 W117 E C59 R21 W4 W14 W96 R112 Q29 Q31 Q18 C5 R1 R2 W37 R228 Q14 C16 C17 R37 R33 E R36 C14 C15 C18 C19 E C4 R229 CN2 Q20 C1 C2 C8 R114 R116 R113 R111 R115 W100 W99 R157 W119 D40 R118 R120 R117 B R35 R34 E R91 W23 W26 W18 W19 B R41 W98 R184 R88 W80 B Q19