Cellphone Signal Problem

There are two sections in network: 1, Rx section. 2, Tx section. all bros plz use manual searching in mobile phone, testing for Rx section and Tx section.
HOW TO FIND WHICH SECTION IS FAULT Tx (or) Rx?

Testing Rx section

use manual search for Testing Rx section, after searching Rx section good condition means it shows network list like Airtel, hutch, (or) any other network list in your area,

If Rx section bad condition after searching it shows NO NETWORK FOUND

1. after searching it shows network list means Rx section is ok.
2. after searching it shows NO NETWORK FOUND or some networks missing means Rx section is faulty.

Testing Tx section

Use manual search for testing Tx section, after searching it shows network list, then you can choose your simcard network, if Tx section is good condition it shows HOME NETWORK SELECTED, if Tx section is fault it shows NO ACCESS.

1. after selecting network it shows HOME NETWORK SELECTED means Tx section is ok.
2. after selected network it shows NO ACCESS means Tx section is fault

Information of Rx section components and ics nokia dct-3 tech

1. antenna switch
2. RF IC ( Hagar ic )
3. AUDIO IC ( cobba ic)
4. crystal oscillator
5. filters
6. VCO (voltage control oscillator)

Information of Tx section components and ics nokia dct-3 tech

1. PF IC (PA IC)

Information of Rx section components and ics nokia dct-4 tech

1. antenna switch
2. filters
3. RF IC
4. crystal oscillator
5. VCO (voltage control oscillator)
6. UEM IC

Information of Tx section components and ics nokia dct-4 tech

1. PF IC (PA IC)

HOW TO SERVICE Rx SECTION FAULT ?

Solution for Rx section no network found fault nokia dct-3 technolagy

1.clean the pcb well and Rehot (if not ok follow one by one solutions)

1. give antenna switch jumper
2. Rehot the RF IC
3. Rehot the AUDIO IC
4. Reball the RF IC
5. change the RF IC
6. change the AUDIO IC
7. change the crystal oscillator

Solution for Rx section NO NETWORK FOUND fault nokia dct-4 technology

1. clean the pcb well and Rehot (if not ok follow one by one solutions)
2. give antenna switch jumper
3. Reheat the RF IC
4. change the crystal oscillator
5. Reball the RF IC
6. change the RF IC
7. Change filters

HOW TO SERVICE Tx SECTION FAULT ?

Solution for Tx section NO ACCESS fault nokia dct-3 technolagy

1. Change the PF IC

Solution for Tx section NO ACCESS fault nokia dct-4 technolagy

1. Change the PF IC

SOLUTION FOR OTHER NETWORK FAULT

Solution for low network coverage, all models

1. give jumper from antenna contact to cabinet antenna
2. change the antenna switch

Solution for dct-3 technology
When switch on the mobile it shows full network after few seconds its goas down

1. flash - Rebuild ime - UI settings (if not ok follow 2nd solution)
2. check the track from battery +ve point to PA IC, if track is ok then change the good PF IC.

Solution for dct-4 technology
When switch on the mobile it shows full network after few seconds its goas down

1. write good pm file (if not ok follow 2nd solution)
2. change the PF IC, if still the problem same check the PF power track to battery +ve point.