After Sales Technical Documentation TROUBLESHOOTING INSTRUCTIONS FOR NHA–2 & NHA–4 Original, 43/96 NMP Part No.
Troubleshooting Instructions After Sales Technical Documentation AMENDMENT RECORD SHEET Amendment Number Page 2 Date Inserted By Comments Original, 45/95
After Sales Troubleshooting Instructions Technical Documentation TROUBLESHOOTING INSTRUCTIONS Contents Introduction General General Chart Logic Fault Receiver Fault 1 Receiver Fault 2 Transmitter Fault 1 Transmitter Fault 2 Earphone Level/Modulation Level Fault Display or Keypad Fault Call Set–up Fault Original, 45/95 Page 4 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 3
Troubleshooting Instructions After Sales Technical Documentation Introduction General The purpose is to define fault block of the module and then find out the broken component. The trouble shooting diagram has been planned so that the fault, whatever it is, can be found by as simple measurements as possible. The flow diagrams give you the overview of the blocks.
After Sales Troubleshooting Instructions Technical Documentation General Chart START No Will turn into local mode ? Logic fault Yes Receiver OK ? No Receiver fault ( SINAD OK ) Yes Transmitter operating No Transmitter fault ( RF power OK ) ? Yes Earphone level / No modulation Earphone level or modulation fault Yes Is display / keypad No Display or keypad fault working ? Yes No Call set–up ? Call set–up fault Yes END Original, 45/95 Page 5
Check : – COFF N1/pin 16 2 Vpp – VBAT N1/pins 1, 5 and 22 4.8 V – GND N1/pins 7, 19 and 24 – CREF N1/pin 6 3.3 V – if OK, change N1 Troubleshooting Instructions Are VL (N1/pin 23) and VA (N1/pin 2) 3.3 V ? Power drops off or does not assume local mode. Check clock signal of N2/pin 61 0.8 Vpp/14.85 MHz OK ? NO Logic Fault Page 6 Logic fault YES NO Check: – solderings of G600 – loading of CLKIN–line – C77 – if OK, change G600 YES Is G600 / VCC 3.
Original, 45/95 Replace duplex filter Z700 Yes TX spectrum OK ? Yes Simplex sens. ( TX off ) OK? Receiver fault Check the operation between the aerial and Z703 Check solderings of R636, C749, C718, C719 and L710. Check also N700/ pins 1 and 2. Check solderings of V601, C600, C602 and C709 Receiver fault 2 No No *measured with 10:1 divider No No No No Transmitter fault Yes Is there level at Z703 – 63dBm* ? Yes Is there at N700/pin 2 – 28dBm*/ 44.
Troubleshooting Instructions After Sales Technical Documentation Receiver Fault 2 Receiver fault 1 *measured with 10:1 divider Check L603 No – 1.9 V. OK ? Check –VMOD line between display module ( or –VOUT pad ) and V603 anode Yes Are N650/ pins 4 and 14 No 2.8 V ? Check : – L605, V605, R646, R647 – loading of N650/pins 4 and 14 Yes Control signals of N650/pins 8, 11, 12, 13, 19 ( pin 8 –17dBm*/ 14.
Original, 45/95 Check the components affecting V805 d.c. operating point Check the critical components of the amplifier V803 No Is there at V804 collector +2dBm* ? No Check the components affecting V804 d.c. operating point Yes Yes Check the operation of G600 and its eeprom values Power OK, but transmitter frequency error Transmitter fault *measured with 10:1 divider Yes Yes Is there at V803 collector –4dBm* ( biggest power ) ? No Check that VCONT at V803 collector is 4 V.
Resistance between N650/pin 17 and V659 cathode is about 5 Kohm Check d.c.voltages Yes V657/c (2.7V) b (2.7V) e (2.0V) V658/c (1.8V) b (1.1V) e (0.5V) OK ? No Yes Troubleshooting Instructions Transmitter Fault 2 Page 10 Transmitter fault 1 Check the critical components of VCO : V659, C663, C659, L651, C675. Check also C686, C637 and N650/pin 15. No Check the components affecting V657 and V658 d.c.
Original, 45/95 pin 27 DAF 140 mVpp 140 mVpp pin 46 XMIC Signals levels of N2 200 mVpp pin 28 FILO 120 mVpp pin 47 ATTO – XMIC line 60 mV / 1 kHz – voice modulation 2.9 kHz – volume 3 – comp. on 200 mVpp pin 29 EXPI 120 mVpp pin 49 COMI 140 mVpp pin 32 EXPO 190 mVpp pin 50 COMO 140 mVpp pin 34 VOLI 190mVpp pin 51 EMPI 330 mVpp pin 35 XEAR 270 mVpp pin 52 EMPO 270 mVpp pin 53 LPIN 330 mVpp X1/pin 9 XEAR 540 mVpp pin 55 MOD SAT 420mVpp ST 1.
Troubleshooting Instructions After Sales Technical Documentation Display or Keypad Fault Display or keypad fault No Change the Display OK ? display module Yes No Display OK ? Check: – X2/pins 1 and 15 ( VBAT ) – X2/pins 4 and 16 ( GND ) – X2/pin 3 ( LCDCLK ) 2Vpp / 80 kHz – X2/pin 7 ( RESET ) 3.
Subscriber data OK ? Yes Check: – the operation of ST signal – the operation of SAT signal – the operation of Transmitter – the operation of TXI line – the operation of Synthesizer – the operation of VCO – if OK, change N2 No If the reprogramming impossible, check D2 control lines and solder joints.
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