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TM
SERV
Microhone
(T91-0657-15)
© 2007-5 PRINTED IN JA PAN
B51-8791-00 (N) 289
Panel (Display)
(A62-1135-03)
Metallic cabinet
(A01-2206-02)
Button knob (VFO,MR)
(K29-9378-03)
Knob (ENC)
(K29-9376-03)
Button knob (7KEYS)
(K29-9381-02)
Front glass (Display)
(B10-2775-12)
Photo is TM-V71A.
Knob (SQL)
(K29-9380-03) x 2
Knob (VOL)
(K29-9377-03) x 2
Button knob (POWER,PM)
(K29-9379-03)
CONTENTS
DISASSEMBLY FOR REPAIR ......................2
CIRCUIT DESCRIPTION ..............................3
SEMICONDUCTOR DATA .........................11
COMPONENTS DESCRIPTION .................14
TERMINAL FUNCTION .............................19
PARTS LIST ...............................................22
EXPLODED VIEW ......................................38
PACKING ....................................................39
ADJUSTMENT ..........................................40
PC BOARD
DISPLAY UNIT (X54-3590-00) ...............60
TX-RX UNIT (X57-731X-XX) .................64
INTERCONNECTION DIAGRAM ..............72
SCHEMATIC DIAGRAM ............................74
BLOCK DIAGRAM .....................................86
LEVEL DIAGRAM ......................................88
OPTIONAL ACCESSORIES .......................90
SPECIFICATIONS ......................................91
fineline6
This product complies with the RoHS directive for the European market.
This product uses Lead Free solder.
fineline6
TM-V71A/V71E
CIRCUIT DESCRIPTION
4
2. Receiver System
2-1. Band A VHF Receiver Circuit
The incoming signal from the antenna passes through a filter circuit and goes to the RF amplifier (Q228). The amplifi ed signal enters the band-pass fi lter. After the signal passes through the band-pass fi lter, it is amplifi ed by another
RF amplifier (Q227) and then passes through the bandpass fi lter before entering the mixer (Q226). The frequency of the signal is converted by the fi rst local oscillator (Upper heterodyne) to generate a 45.05MHz first IF signal. The signal passes through the MCF (XF486), is amplifi ed by the
IF amplifi er (Q495) and then enters the FM IC (IC486).
The signal is converted to the 455kHz second IF signal by the second local oscillator (Upper heterodyne). It is then detected to generate an audio signal.
2-2. Band B VHF Receiver Circuit
The incoming signal from the antenna passes through a filter circuit and goes to the RF amplifier (Q293). The amplifi ed signal passes through the band-pass fi lter and is amplified by another RF amplifier (Q292). It then passes through the band-pass fi lter and goes to the mixer (Q291).
The frequency of the signal is converted by the fi rst local oscillator (Upper heterodyne) to generate a 49.95MHz fi rst
IF signal. The signal passes through the MCF (XF546), is amplified by the IF amplifier (Q551) and then enters the
FM IC (IC546). The signal is then converted to the 450kHz second IF signal by the second local oscillator, which is tripled 16.8MHz (Upper heterodyne). It is then detected to generate an audio signal.
LPF
D134,135
D186,188
ANT
SW
RF AMP
Q228
AIP
SW
IC576
Q229
RF AMP
Q293
AIP
SW
IC576
Q294
BPF
D241~243
L248,249,258
BPF
D238~240
L245,257
RF AMP
Q227
BPF
D232~234
L232,236,250
BPF
D229~231
L232,233,260
MIXER
Q226
MCF
XF486
IF AMP
Q495
X486
45.505MHz
2nd Local OSC
FM IC
IC486
Band A
AF
45.05MHz
CF
Wide
1st Local OSC
MPU
IC918
Band A
BPF
D306~308
L312~314
BPF
D303~305
L309,310,322
RF AMP
Q292
BPF
D297~299
L301,302,323
BPF
D294~296
L297,298,324
MIXER
Q291
MCF
XF546
49.95MHz
IF AMP
Q551
16.8MHz
TCXO
X66
FM IC
IC546
Q547
Tripler x3
2nd Local OSC
Band B
AF
1st Local OSC
CF
Wide
MPU
IC576
SW
IC667
D/A
Band B
CF
Narrow
CF
Narrow
IC918
IC667
D/A
IC577
SW
Fig. 2 Band A and Band B VHF receiver circuit
2-3. Band A UHF Receiver Circuit
The incoming signal from the antenna passes through a filter circuit and goes to the RF amplifier (Q363). The amplified signal enters the band-pass filter. After the signal passes through the band-pass filter, it is amplified by another RF amplifier (Q362) and then passes through the band-pass filter before entering the mixer (Q361).
The frequency of the signal is converted by the fi rst local oscillator (Lower heterodyne) to generate a 45.05MHz fi rst
IF signal. The signal passes through the MCF (XF486), is amplifi ed by the IF amplifi er (Q495) and then enters the FM
IC (IC486). The signal is converted to the 455kHz second IF signal by the second local oscillator (Upper heterodyne). It is then detected to generate an audio signal.
service-repairmanual.com
2-4. Band B UHF Receiver Circuit
The incoming signal from the antenna passes through a filter circuit and goes to the RF amplifier (Q408). The amplifi ed signal passes through the band-pass fi lter and is amplified by another RF amplifier (Q407). It then passes through the band-pass fi lter and goes to the mixer (Q406).
The frequency of the signal is converted by the fi rst local oscillator (Lower heterodyne) to generate a 49.95MHz fi rst
IF signal. The signal passes through the MCF (XF546), is amplified by the IF amplifier (Q551) and then enters the
FM IC (IC546). The signal is then converted to the 450kHz second IF signal by the second local oscillator, which is tripled 16.8MHz (Upper heterodyne). It is then detected to generate an audio signal.
The VHF/ UHF band-pass filter is tuned to the desired frequency according to the BPF voltage output from the D/A
IC (IC667), and is controlled by the MPU (IC918) and the varicap.
J K L M N O
PC BOARD
P Q R S
TM-V71A/V71E
1 fineline6
ED903
D966
D946
D954
D942
DISPLAY UNIT (X54-3590-00) (A/3, B/3, C/3) Component side view (J79-0140-09)
2
3
S911
POWER
D965
D936
D953
D932
D964
D926
D952
D922
D975
D949
D972
D948
D974
D939
D971
D938
Band A
D973
D929
D970
D928
S912
PM
Band B
4
5
6
56
S908
LOW
R942
R943
S909
PF1
S910
PF2
7
8
service-repairmanual.com
5 SQL_A
KEY11
VOL_A 4
SW5V 2
1 GND
CN902
D914
VR901
J79-0140-09 B/3
9
10
11 5 SQL_B
VOL_B 4
KEY12
SW5V 2
1 GND
CN904
D917
12
VR902
J79-0140-09 C/3
13
61
14
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