Tuner Board - Philips MCD139/All versions Service Manual

9-1

TUNER BOARD

TABLE OF CONTENTS
Tuner Adjustment Table .................................................................. 7-1
Circuit Diagram ............................................................................... 7-2
PCB Layout ..................................................................................... 7-3
Electrical Parts List & Voltage List ................................................. 7-4
TUNER ADJUSTMENT TABLE
Waverange Input frequency Input
VARICAP ALIGNMENT
FM
87.5 - 108MHz
(50kHz grid)
FM - RF
108MHz
FM
87.5MHz mod=1kHz
f= 22.5kHz
Use Service Testprogram. By selecting the TUNER TEST test frequencies will be stored as preset frequencies automatically.
1) If sensitivity of frequency counter is too low adjust to max. channel separation
(input signal: stereo left 90% + 9%, adjust output on right channel to minimum)
3) For AM RF adjustments the original frame antenna has to be used!
9-1
Tuned to Adjust Output Scope/Voltmeter
108MHz 7.5V 1V
check
87.5MHz check 1.4V 0.2V
1602KHz check 7.2V 1V
T005
531KHz 1.1V 0.2V
1700KHz check 7.2V 1V
1.1V 0.2V
531KHz T005
106MHz
VC001
MAX MAX
90.1MHz L001
2) RC network serves for damping the IF-filter while
adjusting the other one.