Panasonic KX-TG3521BXB, Service Manual

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KX-TG3521BXB/KX-TG3521BXS/KX-TG3522BXB/KX-TG3522BXS/KX-TGA351BXB/KX-TGA351BXS
12 Measurements and Adjustments
12.1. Things to Do after Replacing IC or X’tal
12.1.1. Preparation
Equipment: Frequency counter
Check Point for measurement: BCK
Checking tolerance: 13.824 MHz ± 100 Hz (Base Unit)/13.824 MHz ± 100 Hz (Handset)
12.1.2. Check and Adjust Frequency (Base Unit)
1. Set up base unit in TEST mode.
2. Press following keys in order to Adjust Crystal mode. [LOCATOR], [LOCATOR], [LOCATOR], [Button 1] (*1), [Button 2] (*1),
[Button 2] (*1), [Button 1] (*1). Check BCK frequency.
3. If the BCK frequency is out of the checking tolerance (± 100 Hz), adjust to Adjustment tolelance (± 30 Hz) by pressing [Button
1] (*1) or [Button 2] (*1) key.
Adjustment Tolerance: 13.824 MHz ± 30 Hz
4. Press [LOCATOR] key to write the new frequency factor in Memory.
5. Turn the power off. Then this value is available.
Note:
(*1) When you check test mode, connect to the external Buttons because base unit has only LOCATOR key. Refer to “For Test
Mode” in
Base Unit Reference Drawing (P.76). -Insert AC adaptor during checking.
Cross Reference:
Adjustment Mode for Base Unit (P.44)
12.1.3. Check and Adjust Frequency (Handset)
1. Set DC power supply to 3.9 V.
2. Set up handset in TEST mode (Adjustment flow).
3. Press [1] key to Adjust Crystal mode (“Clock Adj.” is displayed on LCD). Check BCK frequency.
4. If the BCK frequency is out of the checking tolerance (± 100 Hz), adjust to Adjustment tolelance (± 30 Hz) by pressing [ ] or
[ ] key.
Adjustment Tolerance: 13.824 MHz ± 30 Hz
5. Press [TALK] key to write the new frequency factor in EEPROM.
6. Turn the power off. Then this value is available.
Cross Reference:
Adjustment Mode for Handset (P.49)
12.1.4. Adjust Battery Low Detector Voltage (Handset)
After handset's DSP (IC501) or EEPROM (IC541) replacement, Re-writing Battery Low voltage to EEPROM is required.
With following handset Adjustment Flow, adjust DC power supply and DC voltmeter by the procedure below.
1. Set DC power supply to 3.9 V.
2. Set up handset in TEST mode (Adjustment flow).
3. Press [1] key and [OFF] key to Adjust Batt Low mode. (“Bat Adj.” is displayed on LCD)
4. Change the voltage of the DC power supply to 3.51 V accurately. Check the voltage at P.C. board pads because some voltage
drops occur due to the usage of long or thin cables.
5. Press [TALK] key twice to write voltage value in EEPROM.
6. Press [TALK] key twice to write charge value 1 in EEPROM.
7. Change the voltage of the DC power supply to 4.50 V accurately.
8. Press [TALK] key twice to write charge value 2 in EEPROM.
9. Turn the power off. Then this value is available.
Note:
Refer to Handset Reference Drawing (P.78) for connection of DC power supply and voltmeter.
Cross Reference:
Adjustment Mode for Handset (P.49)