Transmitter Fault - Nokia NSE-6 SERIES Service Manual

NSE–6
Disassembly & Troubleshooting Instructions

Transmitter Fault (3)

Power
Control
TXLEV5
Transmitter working OK
YES
N250 H1, R740
TXC – pulse OK
YES
N540 pin 33 and 34 pulses
are about the same
TXC – pulse:
Oscilloscope picture in Appendix D
Page 30
NO
Transmitter
Fault
NO
Check TXC – line from N250
pin 17, if OK change N250
NO
V700 anode,
DC–voltage ~0.8V
YES
N540 pin 12,
loading ~4 k Ω
YES
Check C709, R707 and
R708, if OK change V700
Technical Documentation
NO
Check VSYN_1 voltage
through R704, R705 and R706
NO
Check C743, if OK
change N540
Original 08/98
PAMS