LG-TM250
9. When Cellular Rx sensitivity isn't normal.
Change the stubby
antenna, bushing or the
RF switch (U100).
Check the stubby antenna,
bushing and the RF switch
(U100).
Are they O.K.?
Setup HHP mode with Joyphone.
>Mode Offline-d
>Band Select (Mode : CDMA)
>Channel (384)
Apply Rx RF signal level of –30 dBm into
RF switch.
START
Rx RF signal appears at
C117?
Change the RFL6000
(U110).
Change the Rx LDO
(U405).
No
Change the VCO (U140).
Change the PLL LDO
(U402).
Rx LO signal appears at
C455?
Change the RFR6000 (U155).
Change the Rx LDO (U405).
Change the PLL LDO (U402).
Change the Main Board.
No
Change the RF SAW
Filter (F112).
Yes
Yes
No
No
Change the Duplexer
(DP101).
Rx RF signal appears at
C513?
Rx RF signal appears at
C121?
Change the SP3T switch
(U520).
Rx RF signal appears at
C507?
No
Yes
No
Yes
Yes
Yes
LG Electronics Inc.
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