Kenwood HM-901 Service Manual page 8

A B
TUNER UNIT (X05-4600-72) : M
1
D1
2
J1
D2
AM ANT
4
3
FM 300Ω GND 2
7
Ω
FM 75 1
8
J2
6
3
2
4
IC1 : LA1832
IC2 : LC72131
IC4 : NJM4565M
Q1 : 2SC2714(R.O)
Q3 : 2SA1586(Y,GR) or
2SA1611(M5,M6)
Q5 : 2SC4116(Y,GR) or
2SC4177(C5,C6)
D1,2,8 : 1SS133 or
HSS104
D3,4 : MTZJ5.1(B)or
UZ-5.1BSB
5
D10 : MA111
CAUTION: For continued safety, replace safety critical components only with manu-
facturer's recommended parts (refer to parts list).
nents. For continued protection against risk of fire, replace only with same type and
rating fuse(s). To reduce the risk of electric shock, leakage-current or resistance
measurements shall be carried out (exposed parts are acceptably insulated from
6
the supply circuit) before the appliance is returned to the customer.
The DC voltage is an actual reading measured with a high impedance type volt-
meter as the AM/FM signal generator is specified to the conditions as shown in the
list below. The measurement value may vary depending on the measuring instru-
ments used or on the product. The value shown in ( ) is actual reading mea-
sured in the AM made.
MODE CARRIER
FREQUENCY
FM 98MHz 1kHz
7
AM 1000(999)kHz 400Hz
C D
RF
L1
L3
1uH
FM FRONT END
A1 (W02-2608-05)
J2 0
D1
R2 C2 C6
TR1
C20 J4 33 3P 4P
ANT1 12P 0
ANT2
R7
100K
GND
C9 C12
2P 12P
TR3
GND
C17
0.01
TR1 :2SK360
TR2~4 :2SC2413K or 2SC2778
D1~3 :1SV225 or HVM16
VT VOLTAGE
LF:LOW FREQUENCY
HF:HIGH FREQUENCY
BAND FREQ. VT VOLTAGE
LF 1.7V
FM
HF 4.1V
LF 1.2V
AM
HF 4.7V
SIGNAL LINE
GND LINE
+B +B LINE
-B -B LINE
indicates safety critical compo-
MODULATION
ANT INPUT
DEVIATION
STEREO 67.5kHz 7.5kHz(Pilot) 60dB
MONO 30% MOD 60dB
E F
OSC
+5V
C3 4P
R43
220
1/4W
VT 4 FM:11.0V
T1
TR2
R42
J1 R10
82
1/4W
VCC 3
0 180 +B
2.1V
TR4
R44 CF1
100
IF-OUT 2
OSC 1
+B +B
1.0V
4.4V
C36
2.5V
27P
IC2
PLL
IC
REFERENCE PHASE DETECTOR
DIVIDER CHARGE PUMP
UNLOCK POWER
DETECTOR ON
RESET
2
C B I/F DATA SHIFT REGISTER LATCH
2.5V
C37
0V 0V 0V 5.1V
22P
ST:4.0V
MONO:0V
+B +B
G H
+12V
+5V
5.1V
+ +
3.7V
2.5V
C4
0.01 (2.1V)
1.8V(2.1V)
R40
1K
TUNE:0V
UNTUNE:4.9V
5.2V
11.2V
2.1V
CF2
2.1V
5.2V
Q1
1.3V 2.1V
AM
IFT
FM IF
L2
AMP
+ R47
15K
+5V +5V
0.2V(1.9V)
C52
47P
R24
5.6K
+5V +5V
5.1V
2.5V(0V) 2.5V(0V) 0V
1.0V
0V
1/2
SWALLOW COUNTER 12bits PROGRAMABLE
1/16,1/17 4bits DIVIDER
UNIVERSAL COUNTER
R32
1.2K
Q3
0V(10.4V)
FM
+B +B
I J
+12V +12V
X X
0V 2.5V 2.4V
(3.0V) (2.0V) (1.0V)
ST:4.2V
MONO:2.7V
IC1
2.1V
FM/AM
3.2V
ST:0V 1.3V SYSTEM
(3.8V)
MONO:4.7V
IC
4.0V
(1.3V) 4.0V(0V)
5.2V
0V(0.6V)
FM/AM
SW
C20 +
0.1 Q5
+
+
5.1V
+
+5V +5V
12.1V
R25
100
1/4W
L4
R26
+5V +12V
560 1uH
1/4W
13.1V
+12V
12.9V(0V)