Philips MC-20 Service Manual page 24

8-3
TUNER BOARD ECO6 (Non Cenelec) - LAYOUT DIAGRAM
1101 A6 1120 A4 1132 A5 2128 C4 2138 C2 3142 D2 5110 B3 5114 A2 5123 D5 7112 C1
1102 B6 1130 B5 2106 C5 2129 B4 2144 B2 5102 D6 5111 B4 5119 C2 5130 D3 9101 A2
1103 D6 1131 D5 2107 B5 2133 D2 2155 C4 5109 A3 5112 A3 5121 B2 5131 D4 9103 B2
1 2
3 4
TUNER BOARD ECO6 Systems non Cenelec /
componentside view
A
B
C
D
1 2 3 4
PCS 104 194
2101 B5 2125 D3 2134 D7
2103 D4 2126 D6 2135 D7
2104 B4 2127 C5 2136 A4
9104 B5 9107 D4 2119 D3 2130 D5 2137 A4
9105 B1 9108 C4 2120 D3 2131 C5 2139 C6
9106 B3 9109 D2 2124 D3 2132 D6 2140 C6
5 6 7 2
TUNER BOARD ECO6 Systems - non Cenelec /
A
A
A
B
FM 75Ω
B
C
A
C
1
C
AM FRAME AERIAL
B D
D
ECO6 System non Cenelec stage .2, 211099
5 6 7
2
These assembly drawings show a summary of all possible versions.
For components used in a specific version see schematic diagram respectively partslist.
8-3
2141 C6 2149 D6 2161 A6 2169 A4 3132 D5 3146 C7 3157 A6 3168 C7 4103 B5 6106 C3
2143 C7 2150 B5 2163 B6 3101 D5 3134 D3 3152 A4 3158 A4 3169 B6 4106 C4 6107 C7
2145 A5 2152 C5 2164 C6 3102 C3 3141 C5 3153 A4 3159 A5 3170 A6 4107 C5 6120 A6
2146 B7 2153 C5 2165 C4 3103 C4 3143 D6 3154 C7 3160 A5 3172 C7 4108 C5 6130 D4
2147 A5 2154 C4 2166 B6 3104 B4 3144 B7 3155 C7 3161 A5 3176 D6 6103 B3 6131 C4
2148 B6 2159 C5 2167 B6 3105 C4 3145 C5 3156 A6 3167 B7 3181 D4 6105 C3 7101 C5
3 4 5 6 7
copperside view
4 3
1 7
2 8
V dd
(not all items shown
in schematic diagram)
2
Vcc2
Vcc1
D 5
ECO6 Systems non CENELEC stage .2, 211099
3 4 5 6 7
TUNER ADJUSTMENT TABLE
( ECO6 FM/MW- and FM/MW/LW - versions with AM-frame aerial )
Waverange Input frequency Input
VARICAP ALIGNMENT
7102 D4
FM
7103 D7
7111 A5 87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz)
MW
FM/AM-version, 10kHz grid
530 - 1700kHz
FM/MW-version, 9kHz grid
531 - 1602kHz
LW
A
153 - 279kHz
MW
K
FM/MW/LW- version, 9kHz grid
531 - 1602kHz
A
FM IF
C
B
10.7MHz, 45mV
FM D
B E
continuous wave
SMD jumper
FM RF
41..
C
FM A
108MHz
87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz) 87.5MHz mod=1kHz
D f=±22.5kHz
(65.81MHz)
VCO
D
98MHz, 1mV
FM A
continuous wave
AM IF
C
450kHz D f=±10kHz
MW
V = 0.5mV
RF
connect pin 6 of
(as low as
IC 7101 (AM Osc.)
possible)
with 3.3kΩ to Vcc
AM AFC
C
MW
continuous wave
V = 2mV
RF
3)
AM RF
4)
MW
1494kHz
B
FM/MW/LW- and FM/MW-version
( 9kHz grid)
558kHz
531 - 1602kHz
LW 198kHz
MW
1500kHz D f = ±30kHz
FM/AM-version, 10kHz grid
V as low as
RF
530 - 1700kHz 560kHz
possible
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 !
Repeat
8-3
Tuned to Adjust Output Scope/Voltmeter
108MHz 5130 8V ±0.2V
87.5MHz 4.3V ±0.5V
check
(65.81MHz) (1.2V ±0.5V)
1700kHz 5123 8V ±0.2V
530kHz check 1.1V ±0.4V
1602kHz 5123 6.9V ±0.2V
1
531kHz check 1.1V ±0.4V
279kHz 5122 8V ±0.2V
153kHz check 1.1V ±0.4V
1602kHz 5123 8V ±0.2V
531kHz check 1.1V ±0.4V
IC 7101
21
5119 2 0 ± 3 mV DC
shortcircuit
2141
to block AFC
108MHz 2155
4
MAX
87.5MHz
5131
(65.81MHz)
1)
98MHz 3142 3 152kHz ±1kHz
IC 7101
36
100nF
5111
5
IC 7101
40
100nF
5112
see f
o
remark 2) symmetric
5114
2 0 ± 2 mV DC
1494kHz 2106
558kHz 5102
5
5103
198kHz
1500kHz 2106
f
o
symmetric
560kHz 5102
ECO6, Sys + PA with frame aerial, 070799
2)
RC network serves for damping the IF-filter while adjusting the other one.
4)
MW has to be aligned before LW.