Kenwood KRC 278 RYG Service Manual

Page 3

KRC713R(K) COVER1,1P( 6/13/00 6:16 PM \°~/° 3 /\

KRC-13Fl,178R,23R,278R,280R

COMPONENT DESCRIPTION

SYNTHESIZER UNIT (X14-613x-xx)

REF. No. FUNCTION OPERATION
ICt SYSTEM u-COM Controls system.
I02 ELECTRIC VOLUME Controls sound volume. Selects each source.
I03 MUTE Controls each mute output.
IC4 POWER IC Amplifies power so that the speaker can drive audio signal.
I05 EQUALIZER AMPLIFIER Equalizer amplifier for cassette tape sound.
I06 RESET Resets power supply.
IC7 RDS DECODER Decodes RDS signal.
049 A00 DETECTION SW Works when ACC operation stops.
050 BACK-UP DETECTION SW Works when the back-up voltage comes less than 9.2V.
051 ,52 BACK-UP 5V DRIVER Works when the backup works.
053 P.ON 5V SW Works when the power comes.
054,55 8V SW Works when the power comes.
056,57 8V DRIVER Works when the power comes.
058,59 ILLUMINATION +B SW Works when the power comes.
060,61 ILLUMINATION +B DRIVER Works when the power comes.
Works when the back-u volta e detection or the chan er mute or
0150 ELECTRIC VOLUME MUTE sw mom mute works. 9 g g
0151 SVR FORCED DISCHARGE SW Works when the amplifier mute works.
Works when the back-u volta e detection or the chan er mute or
0153 PRE OUT MUTE sw mom mute works. 9 g g
/\ 0201 FM +B SW Works when FM mode is being selected.
\ / 0203 AM +8 SW Works when AM mode is being selected.
0260 MOTOR +B SW Works when TAPE mode is being selected.
0261 MOTOR +B DRIVER Works when 0260 works.
0301 'CHANGER RESET SW Works when power supply is being reset and ICES works.
0320 PANEL 5V SW Works when the back-up works and panel is on the unit.
0350 'P-CON. DRIVER Stops during POWER OFF and ALL OFF modes.
0351 P-CON. PROTECTION SW Works when P-CON is being short-circuited on GND.
0352 P-CON. PROTECTION INHIBIT SW Inhibits protection SW function when P-CON works momentary.
0353 P-CON. SW Stops during POWER OFF and ALL OFF modes.
Works when the back-u volta e detection or the chan er mute or
0450,451 PRE OUT MUTE sw mom mute works. 9 g g
0500 AUDIO OUT BUFFER For RDS decorder (IC7).
0501 ,502 AFC TIME CONSTANT SW Works when receiving FM signal. Stops when seeking FM signal.
0503 NOISE BUFFER For noise level detection.