Kenwood TK-2107 User manual

© 2000-05 PRINTED IN JAPAN
B51-8536-00(S) 200
VHF FM TR
TK-
SERVICE M U L
GENERAL.................................................................. 2
REALIGNMENT......................................................... 2
DISASSEMBLY FOR REPAIR................................... 4
CIRCUIT DESCRIPTION ........................................... 5
SEMICONDUCTOR DATA ......................................... 9
DESCRIPTION OF COMPONENTS........................ 10
PARTS LIST............................................................. 11
EXPLODEDVIEW ................................................... 17
PACKING ................................................................. 18
ADJUSTMENT......................................................... 19
PC BOARD VIEWS
TX-RX UNIT (X57-6020-21) ................................ 23
SCHEMATIC DIAGRAM .......................................... 27
BLOCK DIAGRAM .................................................. 31
LEVEL DIAGRAM ................................................... 33
KNB-15A (Ni-Cd BATTERY) ................................... 34
SPECIFICATIONS ................................BACK COVER
Antenna
(T90-0733-05):M3
Cabinet assy
(A02-2448-13)
Knob(VOLUME)
(K29-5255-03)
TK-2107 (16 channels)
CONTENTS
Knob
(CHANNEL SELECTOR)
(K29-5278-03)
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5
TK-2107
1.Frequency configuration
The receiver utilizes double conversion. The first IF is
38.85MHz and the second IF is 450kHz. The first local
oscillator signal is supplied from the PLL circuit.
CIRCUIT DESCRIPTION
ANT
ANT SW RF
AMP
MCF
CF
IF SYSTEM AF
AMP
RX
TX
PA
AMP TX
AMP
PLL
VCO MIC AMP
TCXO
X3
multiply
38 85MHz
450kHz
38.4MHz
12 8MHz
SP
MIC
Fig. 1 Frequency configuration
ANT
D102, D103 BPF RF AMP
Q203 BPF MIXER
Q202 MCF XF200 IF AMP Q201
CF200
IF, MIX, DET
IC200 AF AMP
LPF, HPF
IC300
AF PA AMP
IC302
SP
X3
multiply
Q1
TCXO
1st Local OSC
(PLL)
ANT SW
Fig. 2 Receiver section configuration
The PLL circuit in the transmitter generates the necessary
frequencies. Fig. 1 shows the frequencies.
2.Receiver
The receiver is double conversion superheterodyne,
designed to operate in the frequency range of 216 to 223MHz
(M3 type).
The frequency configuration is shown in Fig. 1.
1) Front - end RF amplifier
An incoming signal from the antenna is applied to an RF
amplifier (Q203) after passing through a transmit/receive
switch circuit (D102 and D103 are off) and a band pass filter
(L208, L209 and L210). After the signal is amplified (Q203),
the signal is filtered through a band pass filter (L203 and L214)
to eliminate unwanted signals before it is passed to the first
mixer. (See Fig. 2)
2) First Mixer
The signal from the RF amplifier is heterodyned with the
first local oscillator signal from the PLL frequency synthesizer
circuit at the first mixer (Q202) to create a 38.85MHz first
intermediate frequency (1st IF) signal. The first IF signal is
then fed through two monolithic crystal filters (MCFs : XF200)
to further remove spurious signals.
3) IF amplifier
The first IF signal is amplified by Q201, and then enters
IC200 (FM processing IC). The signal is heterodyned again
with a second local oscillator signal within IC200 to create a
450kHz second IF signal. The second IF signal is then fed
through a 450kHz ceramic filter (CF200) to further eliminate
unwanted signals before it is amplified and FM detected in
IC200.
4) AF amplifier
The recovered AF signal obtained from IC200 is amplified
by IC300 (1/4), filtered by the IC300 low-pass filter (2/4) and
IC300 high-pass filter (3/4) and (4/4), and de-emphasized by
R303 and C306. The processed AF signal passes through an
AF volume control and is amplified to a sufficient level to drive
a loud speaker by an AF power amplifier (IC302).
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ABCDE FGH I J KLMNOPQRS
1
3
4
5
6
7
8
9
10
11
12
13
14
2
2423
TK-2107
PC BOARD VIEW
TX-RX UNIT (X57-6020-21)
Component Side View
TX-RX UNIT (X57-6020-21) Component Side View
IC100
1 4
8
5
C337
IC302 1
5
10
6
Q307
C332
IC401
1 4
8 5
IC400
IC402
1
3
5
4
4
5
3
1
C527
C507
IC404
IGO
L118
C505
C417
AF
C519
1
4
8
5
TH500
L403
L400
L401
L402
IC500
Q305
F500
C331
C523
C522
VR500
C529
R137
R140
R143
R135
R142
R141
R144
R134
R146
R145
R505
R504
R503
R333 R334
R133
R409
R405
R412
R418
R401
R536
R537
R538
R535
R534
R500
R501
R522
R517
R520
R516
R512
R515
R519
R514
R511 R510
R532
R508
R411
R408
R407
R413
R404
R400
R138
R136
R513 R518
R509
R506
R524
R529
R525
R528
R526
R527
R331
R330
R335 R336
R332
R533
R530
R523
R539
C336
C335
C330
C334
C139
C415
C412
C414
C410
C403
C500
C501
C513
VHF
C512
C511
C509
C510
DEV
C508
C525
C530
C514
C515
C416
C400
C404
C134 C132
C141
C407
C413
C516
C520
C518
C524
C521
C327
C333
C526
C517
C411
R131
R130
R132
MIC500
MIC
IC403
125
75 51
26
50
100
76
X400
R414
R415
R421
R423
C418
1
5
10
6
SB
C420
C422
C425
R502
C502
C503
Q106
Q104
B
Q103
C115
R122
R126
C112
R119
C127
R416
VR1
BAL
R431 R430
R6
R310
L502
Q108
Q304
Q306
Q403
Q501
Q502
Q503
L500
D500
J72-0686-02
D501
C504
VR501
D400
D401
C531
R540
R417
R327
S
D
G
C409
C408
R521
R541
Q109
Q107
Q402
R339
CN400
Q504 CV
R507
R531
C533
R542
R548
R125 R124
C130
Component side
Foil side
Pattern 1
Pattern 2
Pattern 3
Pattern 4
2SC4988
M38267M8L241GP DTA114EE
DTA114YE
DTA123JE
DTA143ZE
DTA144EE
DTC114EE
DTC114TE
DTC144EE
2SA1362
2SC4617
2SC5108
FP210
B1 C1
C2
EC
B2
B
C
E
MB15A02
DA221UMC4
.ON.feRsserddA
001CIF8
203CIL8
004CIQ7
104CIP4
204CIQ8
304CIO6
404CIR4
005CII6
301QE7
401QE8
601QH8
701QH8
801QI8
901QG8
403QM9
503QM8
603QK9
703QK9
204QQ5
304QQ6
105QL6
205QK6
305QG5
405QO4
004DC5
104DC5
005DH4
105DH5
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