Adjustment - Sharp WF-971T Service Manual

WF-971T
MECHANISM SECTION
• Driving Force Check
ADJUSTMENT
TUNER SECTION
fL:
Low-range
frequency
fH: High-range frequency
Torque Meter
Specified Value
Play: TW-2412
Tape 1: Over 50g
Tape 2: Over 60 9
• Torque Check
Torque Meter
Specified Value
Tape 1 Tape 2
Play: TW-2111 30 to 60 g.cm
30 to 60 g.cm
Fast forward: TW-2231
55 to 120 g.cm 80 to 135 g.cm
Rewind: TW-2231 55 to 120 g.cm 80 to 135 g.cm
• Head Azimuth
Test Tape
Instrument Connection
MTT-114
Headphones Socket
(Load resistance: 32 ohms)
• Tape Speed (Normal only)
Test Tape
Adjusting
Specified Instrument
Point Value
Connection
MTT-111 Tape 1.2: VR501 3,000 ± 60 Hz
Headphones
socket(Load
resistance:
32 ohms)
TAPE SECTION
Position of each switch or control
Volume control
Max
Beat cancel A
Function/Power Tape/Stand-by
Dubbing speed/Built-in Microphone
OFF/Mic ON
• Bias Oscillation Frequency
Specified Value
Beatcancel A: 100±4kHz
B: 94±4kHz
C: 104 ±4 kHz
• Playback Amplifier Sensitivity Check
Test Tape
Specified Value
Instrument Connection
MTT-118 1.3 V ± 3 dB
Speaker terminal
(Load resistance: 3 ohms)
• AM IF/RF
Specified
Instrument
Test Stage
Value/Adjusting
Point
Connection
IF
T3 Input: Antenna
Output: Pin 3 of IC2
MW Band fL: L6
Input: Antenna
Coverage fH: TCa Output:
MW Tracking
fL (600 kHz):
Headphones Socket
L3(MW)
(Load resistance:
fH (1,400 kHz):
azohms)
TC7
LW Band fL(148.5kHz): L7
Coverage
fH(283.5kHz): TC4
LW Tracking fL: (LW)
fH : TC2
• FM IF/RF
Specified
Instrument
Test Stage
Value/Adjusting
Connection
Point
IF T1
Input: Antenna
Detection T2
Output: Pin17 of iC2
Band Coverage fL: L2
Input: Antenna
fH: TC6
Output:
Tracking fL (88.0 MHz):
Headphones Socket
L1
(Load resistance:
fH (108.0 MHz):
320hms)
TC5
• VCO Frequency
Test Stage Specified Value
Instrument
Connection
VR1 76 kHz ± 200 Hz Pin 13 of IC2
-6-