Page 73 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

Antenna Switch

Antenna switch is help to filtering frequency Bands as 900Mhz, 1800Mhz and connect Rx, Tx ( Receiver and
Transmitter). Therefore when damage this IC we can see faults as following

i Signal Drop

ii No Network found
iii Some Frequency band are not worked properly
RF Processor
RF (Radio Frequency) Processor is a main IC in your phone PCB. This IC is used for processing Rx and Tx
signal (for Modulating and Demodulating). Sometimes it makes a low frequency clock signal is used to start CPU
functions. Therefore when damage this IC we can see faults as following.

Power on failure
i Signal drop
ii No network
iii Caller drop
iv Rx or Tx or both are not work properly
v Battery empty quickly and phone will heat

Power IC
Power IC distribute current to all the components and IC in PCB. we can see some times some applications are
not working because of Power IC is damage.(when power ic not distribute current for circuits that circuits are not
worked).

i Power on failure
ii Battery empty quickly
iii Phone will heat
iv Insert Sim
v No Charging
vi Some applications are not worked properly
vii Auto Restart

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CITS : E & H - Electronics Mechanic - Exercise 134