Nokia specific trouble shooting of five cases |
| Time£º2015-05-23 19:29:25 Source£ºNetwork Author£ºUnknown Clicks£º1515 |
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stAservice manual download site
¤Ÿ [4]8250 machines with poor reception.stAservice manual download site
A new 8250 machine, the customer said that has not dropped, but the signal is very poor, no signal weak signal places. So manually searching the net, searching for a long time without a search. Judge faults appear in the receiving part, doubt filter failure. On the receiving transmission channel filter wire, also was searching the net. Cold solder joint, or failure of the filter has ruled out the possibility of to check if measured 13MHz normal, when measured IQ of intermediate frequency output signal waveform found abnormal, doubt if IC cold solder joint. Repair welding system using a heat gun, everything is normal.stAservice manual download site
¤Ÿ [5]3310 machines are often automatically shut down.stAservice manual download site
A 3310 machine often automatically shut down for no reason, lying motionless on the table, he'll shut it down and start thought it was a bad battery contact, after dealing with fault still, suspected to be a power failure, but the power supply IC replanting is not. After looking up this type of dormancy is caused by poor design of circuit, 13MHz Crystal needs to be below the R559 parameters changed little resistance. R599 changed after 2k, mobile phones are no longer automatically shutdown, troubleshooting.stAservice manual download site
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