Chapter 2. Adjustments - Sharp QT-MP5W Service Manual

QT-MP5W

CHAPTER 2. ADJUSTMENTS

[1] Tuner Adjustments
Use a plastic screw driver for adjustments.
Adjust the intermediate frequency of AM to the frequency of ceramic filter.
Set of unit
Supply voltage : DC 12V
Speaker impedance : 8 ohms
Standard output : 50 mW
Function select : TUNER
Parts Location:
a. AM adjustment
Adjusting
Step
Circuit
terminal by sweep
1 IF
generator, it place to
Tuning cover Connect AM SG to
2
range
Connect AM SG to
3 Tracking
b. FM adjustment
Adjusting
Step
Circuit
1 IF
generator to C139
Tuning cover Connect FM SG to
2
range D102(+) & D101(-)
Connect FM SG to
3 Tracking
D102(+) & D101(-)
L101
CT101
C129
L102
R125
Band: AM
Connections
Input Output
Close the output
Connect VTVM to
C129(-)
AM ANT
Connect VTVM to
test loop R144
Connect VTVM to
test loop speaker terminals
Band: FM
Connections
Input Output
Connect sweep Connect VTVM to
C129(-)
Connect VTVM to
R125
Connect VTVM to
speaker terminals
SG Position of
Frequency Tuning Dial
450 KHz 520 KHz
520 KHz 520 KHz
1710 KHz 1710 KHz
600 KHz 600 KHz
1400 KHz 1400 KHz
FM Dummy antenna: 75 ohms unbalance
SG Position of
Frequency Tuning Dial
10.7 MHz 90.00 MHz
87.90 MHz 87.90 MHz
107.90 MHz 107.90 MHz
90.00 MHz 90.00 MHz
106.00 MHz 106.00 MHz
2 – 1
R144
CT102
T102
T101
T103
VTVM
Adjustment
Oscilloscope
T103
T101 VT: 1.0+-/0.05V
VT: 7.2+-/0.5V
T102
Max.
TC102
VTVM
Adjustment
Oscilloscope
L102 VT: 1.8+-/0.1V
VT: 7.0+-/0.5V
L101
Max.
TC101