Philips AZ 2048, Service Manual

Page: 10 / 35

3 - 6
VARICAP ALIGNMENT
FM RF
FM IF
VCO
AM IF
AM RF
3)
108MHz
87.5MHz
(65.81MHz)
87.5MHz
(65.81MHz)
87.5MHz
(65.81MHz)
279kHz
153kHz
1602kHz
531kHz
5130
check
5122
check
5123
check
8V –0.2V
4.3V –0.5V
(1.2V –0.5V)
8V –0.2V
1.1V –0.4V
8V –0.2V
1.1V –0.4V
1494kHz
558kHz
560kHz
1500kHz
5105
LW ferrite coil
198kHz
1494kHz
558kHz
560kHz
1500kHz
198kHz
2106
5104
MW ferrite coil
5104
MW ferrite coil
2106
3142 152kHz –1kHz
1)
98MHz
5112
MAX
FM
87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz)
LW
153 - 279kHz
MW
FM/MW/LW- version, 9kHz grid
531 - 1602kHz
1700kHz
530kHz
5123
check
8V –0.2V
1.1V –0.4V
1602kHz
531kHz
5123
check
6.9V –0.2V
1.1V –0.4V
108MHz 108MHz 2155
5131
MW
FM/AM-version, 10kHz grid
530 - 1700kHz
FM
MW
LW
98MHz, 1mV
continuous wave
450kHz
connect pin 6 of
IC 7101 (AM Osc.)
with 2.2k‰ to Vcc
Use Service Testprogram. By selecting the TUNER TEST test frequencies will be stored as preset frequencies automatically.
4
1
3
5
5
A
A
5119 FM
10.7MHz, 45mV
continuous wave
2 D
mod=1kHz
∆ f=–22.5kHz
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)
Repeat
ECO6, general with ferrite antenna, 070799
TUNER ADJUSTMENT TABLE
( ECO6 FM/MW- and FM/MW/LW - versions with ferrite antenna)
∆ f=–10kHz
V
RF
= 0.5mV
C
see
remark 2)
220R
100nF
36
IC 7101
220R
100nF
40
IC 7101
2141
shortcircuit
to block AFC
21
IC 7101
max.
symmetric
f
o
AM AFC
MW
C
continuous wave
V
RF
= 2mV
5111
5114
2
0 – 2 mV DC
0 – 3 mV DC
MW
FM/MW/LW- and FM/MW-version
( 9kHz grid)
531 - 1602kHz
B
∆ f = –30kHz
V
RF
as low as
possible
max.
symmetric
f
o
MW
FM/AM-version, 10kHz grid
530 - 1700kHz
2)
RC network serves for damping the IF-filter while adjusting the other one.
3)
LW has to be aligned before MW.
Waverange Input frequency Input Tuned to Adjust Output Scope/Voltmeter
FM
87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz)
FM/MW-version, 9kHz grid
531 - 1602kHz
(as low as
possible)