Yamaha cr 1000

Page 2

CONTENTS

CIRCUIT DESCRIPTION
SPECIFICATIONS
EXTERNAL VIEW
FRONT PANEL
REAR PANEL (U.S.&CANADIAN MODEL
REAR PANEL (EUROPEAN MODEL
INTERNAL VIEW

PARTIAL DISASSEMBLY
DIAL MECHANISM .......
MEASUREMENT AND ADJUSTMENT
TUNER SECTION ................................................................................................................... 15
AUDIO SECTION
EQ AMP CIRCUIT BOARD ADJUSTMENT
MAIN AMP CIRCUIT BOARD ADJUSTMENT
PRINTED CIRCUIT BOARD 8i SPECIAL REPLACEMENT PARTS LIST
TUNER CIRCUIT BOARD
EOUALIZER AMP CIRCUIT BOARD
FUNCTION CIRCUIT BOARD ............
TAPE MONITOR SWITCH CIRCUIT BOARD
MODE SWITCH CIRCUIT BOARD ......
TONE CONTROL AMP CIRCUIT BOAR
TONE CONTROL SWITCH CIRCUIT BO
TONE CONTROL VOLUME CIRCUIT BOAR
FILTER AMP CIRCUIT BOARD
LOUDNESS CIRCUIT BOARD~
FILTER SWITCH CIRCUIT BOARD
MIC AMP CIRCUIT BOARD .......
MIC VOLUME CIRCUIT BOARD
MAIN AMP CIRCUIT BOARD ,
LIGHT EMITTING DIODE CIRCUIT BOARD
POWER CIRCUIT BOARD ..........
REAR PANEL CIRCUIT BOARD
BLOCK DIAGRAM .................................
OVERALL SCHEMATIC DIAGRAM .............................
PARTIAL CHANGES MADE ACCORDING TO DESTINATIONI

CIRCUIT DESCRIPTION

0 AUTO-TOUCH AFC OFF CIRCUIT

gm The human body's electric current (G) is detected by the
m .. I I Tm A *3 , tuning knob and amplified by the pre-amplifier. which
"733; EH-v-r #19: . then feeds it to D1 and D2.
é gt 5i This current is then supplied to the base of the Trl18,
J, . . I. 1 switching it and the AFC signal on. while the AFC
HWMWW' circuit goes off.

When the station is tuned in and the tuning knob re-
leased. the current going to the bese of the TH 13 goes

W. nxv
ammo.

I mic off and the AFC circuit switches on for steady FM
5? = listening.
I At the same time, the LED illuminated by the IF signal

goes off to signal that the AFC circuit is off. This happens
because DI and DZ (mentioned above) feed current to
the base of Tr109, lowering the Tr109 C-E impedance
and thus reducing the Tr110 base collector current.