Teac AG-370 User manual

AAGG--337700
SERVICE MANUAL
AM/FM Stereo Receiver
Effective : April, 2003 S-0091A
NOTES
●PC boards shown are viewed from parts side.
●The parts with no reference number or no parts number in the
exploded views are not supplied.
●As regards the resistors and capacitors, refer to the circuit diagrams
contained in this manual.
●£Parts marked with this sign are safety critical components. They
must be replaced with identical components - refer to the appropriate
parts list and ensure exact replacement.
CONTENTS
1 SPECIFICATIONS ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・2
2 ADJUSTMENTS AND CHECKS ・・・・・・・・・・・・・・・・・・・・・・・・3
3 EXPLODED VIEWS AND PARTS LIST ・・・・・・・・・・・・・・・・・6
4 PC BOARDS AND PARTS LIST ・・・・・・・・・・・・・・・・・・・・・・・・8

1 SPECIFICATIONS
−2−
Amplifier Section
Output Power .... 50 + 50 watts RMS (0.9 % THD, 1 kHz, 8 ohms)
Total Harmonic Distortion.................... 0.05 % (at 45 watts,1 kHz)
Input Sensitivity/Impedance .................. PHONO: 4 mV/22 kohms
LINE: 270 mV/20 kohms
Frequency Response.................... PHONO: 20 Hz–20 kHz, +/–3 dB
LINE: 20 Hz–30 kHz, +1/–3 dB
Signal-to-Noise Ratio.............................................. PHONO: 60 dB
LINE: 68 dB
Tone Control .......................................... BASS: +/–9 dB at 100 Hz
TREBLE: +/–7 dB at 10 kHz
Loudness Control (Volume at –40 dB Position)..............................
+7 dB at 100 Hz, +5 dB at 10 kHz
FM Tuner Section
(Without notes 98.1 MHz, 65 dBf)
Tuning Range .................... 87.5 MHz–108.0 MHz (100 kHz steps)
Usable Sensitivity (IHF) ............................................ Mono: 20 dBf
50 dB Quieting Sensitivity................ Mono: 39 dBf, Stereo: 46 dBf
Capture Ratio ...................................................................... 2.8 dB
Image Rejection Ratio .......................................................... 20 dB
AM Suppresion Ratio............................................................ 48 dB
Harmonic Distortion (1 kHz) .............. Mono: 0.4 %, Stereo: 0.5 %
Frequency Response................................ 30 Hz–15 kHz, +2/–3 dB
Stereo Separation (1 kHz) .................................................... 35 dB
Signal-to-Noise Ratio ........................ Mono: 57 dB, Stereo: 55 dB
AM Tuner Section
Tuning Range .......................... 520 kHz–1,720 kHz (10 kHz steps)
Usable Sensitivity ............................................................ 55 dB/m
Total Harmonic Distortion .................................... 1 % at 85 dB/m
Signal-to-Noise Ratio............................................................ 48 dB
General
Power Requirements.................................. 120 V/230 V, 50-60 Hz
Power Consumption ............................................................ 120 W
AC Outlet .......................... Unswitched x 1, 100 W max (1 A max)
Dimensions (W x H x D) ........................ 17-1/8" x 5-1/8" x 12-5/8"
(435 x 130 x 320 mm)
Weight (net) .................................................. 15-7/16 lbs (7.0 kg)
Standard Accessories .................................. AM Loop Antenna x 1
FM ”T” Type Antenna x 1
•Design and specifications are subject to change without notice.
Voltage Conversion
(General export models only)
Be sure to remove the power cord from the AC outlet before
repositioning the voltage converter switch.
1. Locate the voltage selector on the rear panel.
2. Using a flat-bladed screwdriver, set to the appropriate
230V or 120V position according to your area.
IN NORTH AMERICA USE ONLY ON 120 V SUPPLY.

2 ADJUSTMENTS AND CHECKS
−3−
2-1 AMPLIFIER SECTION
Bias Current Adjustment
1. Turn the unit on, and set the input selector switch to "CD".
2. Set 7VR1 and 7VR2 to the center position.
3. Connect the DC voltmeter as shown below after preheating for
10 minutes, and adjust 7VR1 (Lch) so that the voltage
becomes 3.3±1.3mV.
4. Adjust 7VR2 (Rch) in the same way.
7VR17VR2
7R46 7R44 7R45 7R43
0.33/5W 0.33/5W 0.33/5W 0.33/5W
MAIN PCB
DC voltmeter DC voltmeter

−4−
ITEM SETTING ADJUSTMENT
POINTS ADJUST
2. AM Sensitivity
∫
600 kHz/1500 kHz
50 dB/m
400 Hz (30 % Mod)
ç
REC OUT
AM 600 kHz 2T1 (BLK) Max.
3. AM IF
∫
1000 kHz
50 dB/m
400 Hz (30 % Mod)
ç
REC OUT AM 1000 kHz 2T3 (WHT) Max.
4. FM Sensitivity
∂
90 MHz
10~20 dBf
1 kHz (100 % Mod)
ƒ
REC OUT FM 90 MHz 2L2 (4.5T) Max.
5. FM Distortion
∂
98 MHz
60 dBf
1 kHz (100 % Mod)
©
REC OUT FM 98 MHz 2T4 (PINK) Min. distortion
6. FM Stereo
∂é
98 MHz
60 dBf
Stereo signal L-R
©
REC OUT FM 98 MHz 2T5, 2T6 Min. distortion
1. VT Adjust
å
2R19 (VT)
2J2 (GND)
FM 87.5 MHz 2L3 (3.5T) DC 1.0±0.05V
INPUT OUTPUT AG-370
After adjusting 2TC2, readjust 2T1 at 600 kHz.
AM 1500 kHz 2TC2 Max.
AM 1720 kHz
AM 530 kHz
FM 108.0 MHz
Check
2T2 (RED)
Check
≦8.0V
DC 1.1±0.05V
DC 8.0±0.5V
2-2 TUNER SECTION

−5−
AC Voltmeter
FM Signal Generator
Stereo Signal Generator
Distortion Analyzer
D
E
G
F
AC Voltmeter
AM Signal Generator
B
C
AM Loop
Antenna
60cm
2T3
2T6
2T5
2T2
2T1
2T4
2L2
2L3
2TC2
2R19
2J2 TUNER PCB
+−
DC Voltmeter
A

3 EXPLODED VIEWS AND PARTS LIST
−6−
1
2
34
5
6
7
8
9
q
w
e
r
t
y
u
i
o
p
a
s
d
f
g
h
j
k
l
;
z
x
c
v
b
n
m
,
.
/
!
@
#
$

−7−
EXPLODED VIEW LIST
REF.NO. PARTSNO. DESCRIPTION REMARKS
1 9A06536200 MASTERVRKNOB 53W360900
2 9A06900300 INDICATOR 510104200
3 9A09581400 TONECONTROLKNOB 530503000
4 9A09580800 DISPLAYLENS 510503600
5 9A09580700 PANEL 510503500
6 9A09580900 FUNCTIONKEY 530502500
7 9A09581200 MEMORYKEY 530502600
8 9A09581000 BANDKEY 530502900
9 9A09592000 SILICONRUBBER,T0‑3P2 322228370
10‑1£9A09590200 TR,2SD1047E 230104705
10‑2£9A09590300 TR,2SB817E 230817005
11 9A09581100 TUNINGKEY 530502800
12 9A06536000 LOUDKNOB 53W360700
13 9A09581300 AUTO/MANUALKEY 530502700
14 9A09592900 VFDDISPLAY 250370000
15 9A09579810 HEADPHONOPCBASSY 033700601
16 9A09579910 SELECTPCBASSY 033700401
17 9A07063400 SPEAKERSWITCHKNOB 53W361000
18 9A09580010 SELECTPCBASSY 033700501
19£9A06602800 POWERSWITCH 180222501
20 9A06535900 POWERKNOB 530049400
21 9A09579410 CONTROLPCBASSY 033700201
22 9A06536400 LEG(GOLD) 540082601
23 9A06536300 LEG(BLACK) 540082600
24 9A09581600 BOTTOMCOVER 520504800
25 9A06901000 SIDEBRACKET(L) 52W360300
26 9A09581800 SIDEBRACKET(R) 520505100
27 9A09581900 TOPCOVER 520505000
28 9A09579310 MAINPCBASSY 033700101
29 9A09591800 HEATSINK(A) 560502100
30 9A06901200 H/SBRACKET 540082800
31 9A09581700 REARCOVER 520504900
32£9A09580100 POWERTRANSFORMER 157631522
33 9A06904300 GNDTERMINAL,M3 320018601
34£9A06900600 CORDBUSHING 550011700
35£9A06602900 ACSOCKET 26CS18401
36 9A07064400 SPACERSUPPORT 550098819
37 9A09579510 TUNERPCBASSY 033700301
38 9A09591700 CABLECLIP 550505500
39 9A09591600 PCBSUPPORT 550505200
40 9A06900700 NAMEPLATE 510104300
41£9A09580200 ACPOWERCORD 210183011
42 9A09579610 POWERSOCKETPCBASSY 033700701
43 9A09579710 POWERSELECTSWPCBASSY 033700801
44£9A09587200 C,275V0.01UF 136M103M2
INCLUDED ACCESSORIES
REF.NO. PARTSNO. DESCRIPTION REMARKS
9A09471700 OWNER'SMANUAL,EFSP 600520205
9A06902500 FMANT 59W360100
9A06902600 AMANT 59W360200

−8−
4 PC BOARDS AND PARTS LIST
MAIN PCB

−9−
SP SEL PCB SP SEL PCB HEADPHONE PCB POW SEL PCB POWER PCB
FRONT PCB TUNER PCB

MAIN PCB ASSY
REF.NO. PARTSNO. DESCRIPTION
9A09579310 MAINPCBASSY
9A09592100 MAINPCB
9A06534100 SPJACK
9A06534200 RCAJACK,6P
9A06534300 RCAJACK,4P
9A06896100 FUSECLIP
9A06897300 LEADPIN,3P
9A06901200 H/SBRACKET
9A09591600 PCBSUPPORT
9A09591700 CABLECLIP
9A09591800 HEATSINK(A)
9A09591900 HEATSINK(B)
9A09592000 SILICONRUBBER,T0‑3P2
1C1£9A09586700 C,ELEC35V100UFM
1C4‑5£9A09586600 C,ELEC25V2200UFM
1C12£9A09586500 C,ELEC25V100UFM
1C14‑15£9A09587000 C,ELEC58V6800UFM
1D1‑8£9A09589300 DIODE,IN4004
1D9‑12£9A09589400 DIODE,IN5404
1D13‑14 9A09589500 DIODE,IN4148
1D15‑18£9A09589300 DIODE,IN4004
1D19 9A09589100 DIODE,ZENER24V1W
1FU1‑2£9A09591200 FUSE,5A250VSLOWBLOW
1N1£9A09590800 IC,L7812CV
1N2£9A09590900 IC,L7912CV
1N3£9A09590700 IC,L7805CV
3D1‑2 9A09588800 DIODE,ZENER6V81/2W
3N1 9A09590400 IC,TC4052BP
3N2 9A09590500 IC,TC4066BP
3V1‑3 9A09589600 TR,2SC1815GR
4N1 9A09590600 IC,4560D
5N1 9A09590600 IC,4560D
6N1 9A09590600 IC,4560D
7C28£9A09587100 C,ELEC63V47UFM
7D1‑4 9A09589000 DIODE,ZENER24V1/2W
7D5‑6 9A09589500 DIODE,IN4148
7D7 9A09589200 DIODE,ZENER30V1/2W
7D8 9A09589500 DIODE,IN4148
7D9 9A09588900 DIODE,ZENER12V1/2W
7L1‑2 9A09591000 COIL,SPRING1.5UH
7R43‑46£9A09585600 R,CEMENT5WR33J
7R61‑62£9A09585400 R,2W6R1J
7R70£9A09585300 R,0.5W100J
7R77‑78£9A09585500 R,2W10J
7V1‑4 9A09589700 TR,2N5551
7V5‑10 9A09589800 TR,2N5401
7V11‑14 9A09589700 TR,2N5551
7V15‑16 9A09589900 TR,3DA4381
7V17‑18 9A09590000 TR,3CA1667
7V19‑20£9A09590200 TR,2SD1047E
7V21‑22£9A09590300 TR,2SB817E
7V23‑24 9A09589700 TR,2N5551
7V25 9A09589800 TR,2N5401
7V26‑29 9A09590100 TR,2SC8050D
7VR1‑2 9A09585700 VR,SEMI‑FIXED300J
REL1 9A09591100 RELAY,12V5A
CONTROL PCB ASSY
REF.NO. PARTSNO. DESCRIPTION
9A09579410 CONTROLPCBASSY
9A09593800 FRONTPCB
9A09592900 VFDDISPLAY
9A09593900 VFDSHIELDCASE
6S1 9A09593000 SW,LOUDNESS
6VR1‑2 9A06534400 VR,100KBX2
6VR3 9A06604000 VR,50KAX2
6VR4 9A06534500 VR,100KW
8D1 9A09589500 DIODE,IN4148
8D2 9A09592400 DIODE,ZENER5V11/2W
8D3‑8 9A09589500 DIODE,IN4148
8G1 9A09592800 OSC,CRYSTAL4.433M
8N1 9A09592500 IC,HT48R50A‑1
8N2 9A09592600 IC,HT24LC02
8N3 9A09592700 IC,PT6312LQ
SW1‑20 9A09593100 SW,TACT
TUNER PCB ASSY
REF.NO. PARTSNO. DESCRIPTION
9A09579510 TUNERPCBASSY
9A09625000 TUNERPCB
9A09625100 TUNERSHIELDCASE
2D1‑2 9A09589500 DIODE,IN4148
2G1 9A09622100 FILTER,CERAMICL10.7MS2R
2G2 9A09622200 FILTER,CERAMICSFU450B
2G3 9A09622100 FILTER,CERAMICL10.7MS2R
2G4 9A09622300 OSC,CRYSTAL4.5MHZ
2L1 9A09622400 COIL,SPRING3.5TM4.5
2L2 9A09622500 COIL,SPRING4.5TM3.5
2L3 9A09622600 COIL,SPRING3.5TM3.5
2L4 9A09622700 INDUCTOR,AL0410102
2L5 9A09622800 INDUCTOR,AL0410221
2N1 9A09622900 IC,TA2149N
2N2 9A09623000 IC,TC9257F
2T1 9A09623800 IFT,AMRF10B(BLK)
2T2 9A09623900 IFT,AMOSC7B(RED)
2T3 9A09624000 IFT,AMIFT7B(WHT)
2T4 9A09624100 IFT,FMDET7B(PNK)
2T5‑6 9A09624200 IFT,MPX8B(BLK)
2TC2 9A09624300 SVC,CYM1‑2/7
2V1 9A09624400 FET,2SK161GR
2V2 9A09624500 TR,2SC9018I
2V3 9A09624600 TR,2SC9014C
2V4‑5 9A09589600 TR,2SC1815GR
2V6‑7 9A09624600 TR,2SC9014C
2V8 9A09624700 TR,2SC9018H
2VD1‑2 9A09624800 DIODE,VARACTORV1043
2VD3‑4 9A09624900 DIODE,VARACTORV149B
2X1 9A07129000 ANTJACK
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