Panasonic KX-TG7841S Service Manual page 41

KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680
10.1.5.2. Handset
Does Handset link with Base Unit?
(Properly working unit)
NO
Is the voltage of TP VBAT about 2.2~2.8 V?
YES
Is the voltage of TP VDDC about 1.2 V?
YES
Is the voltage of TP 3.0 V about 3.0 V?
YES
Does the RF clock (CLK) oscillate: 13.824 MHz
in Handset Test Mode?
YES
Check the RF part
Cross Reference:
Power Supply Circuit/Reset Circuit (P.23)
Check the RF part (P.42)
Note:
Refer to Things to Do after Replacing IC or X'tal (P.58)(P.65) for Handset.
*1 How to adjust the frequency of X1:
To see the frequency, execute the command "SFR", then check the TP_CKM (IC1-57pin).
To adjust frequency, send command "SFR
YES
Handset is OK. Check Base Unit.
NO
Check the batteries.
NO
Check around Power Supply Circuit/Reset Circuit.
NO Check around X1 and RF module and adjust
clock frequency.
"until the frequency counter becomes13.824 MHz±55HZ.
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