Adjustment - Sharp XL-3000 Service Manual

XL-3000/3000C
TUNER SECTION
fL: Low-range frequency
fH: High-range frequency
• AM IF/RF
Signal generator: 400 Hz, 30%, AM modulated
Frequency Frequency Display
AM IF 450 kHz 1,620 kHz
AM Band — 522 kHz
Coverage
AM 990 kHz 990 kHz
Tracking
*1. Input: Antenna, Output: Speaker Terminal
*2. Input: Input is not connected,
• FM RF
Signal generator: 1 kHz, 75 kHz dev., FM modulated
Test Stage Frequency
Frequency
Display
FM Band — 87.5 MHz
Coverage
FM RF 98.00 MHz 98.0 MHz
(10~30 db)
*1. Input: Antenna, Output: TP301
*2. Input: Antenna, Output: Speaker Terminal
FM
75
SO301
OHMS
ANTENNA
TERMINAL
TP301
20
IC302
FM OSC.
FM Band
Coverage fL
VR351
FM Mute
Level
T351
AM IF
Figure 10-1 ADJUSTMENT POINTS

ADJUSTMENT

Setting/
Instrument
Adjusting Connection
Parts
T351 *1
(fL): T306 *2
1.1 ± 0.1 V
(fL): T302 *1
Output: TP301
Setting/ Instrument
Adjusting Connection
Parts
(fL): L303 *1
3.4 ± 0.1 V
L302 *2
TUNER PWB-A2
AM
GND
IC301
1
L302
L303
T304
FM IF
T306
AM Band
IC303
Coverage fL
• FM Mute Level
Signal generator: 1 kHz, 40 kHz dev., FM modulated
Frequency Display
98.00 MHz 98.00 MHz
(30 dBµV)
*1. Adjust so that an output signal appears.
• FM Detection
Signal generator: 10.7 MHz, FM sweep generator
Test Frequency
Stage
FM IF 10.7 MHz 98.0 MHz
• Setting the Test Mode
Keeping the FF/FWD button and MEMORY/SET button
pressed, turn on POWER. Then, the frequency is initially set
in the memory as shown in Table. Call it with the VOLUME UP/
DOWN button to use it for adjustment and check of tuner
circuit.
Preset No. FM
1 87.5 MHz
2 108.0 MHz
3 98.0 MHz
4 90.0 MHz
5 106.0 MHz
FM ANT.
FM RF
T302
AM
Tracking fL
– 10 –
Adjusting
Instrument
Parts
Connection
VR351*1 Input: SO301
Output: Speaker
Terminal
Frequency Setting/ Instrument
Display Adjusting Connection
Parts
T304(Turn Input: Pin 1 of
the core of IC301
T304 fully
counter-
clockwise.)
Preset No.
6 530 kHz
7 1,720 kHz
8 990 kHz
9 600 kHz
10 1,400 kHz
AM