User's Manual

Table Of Contents
October 14, 2003 6881094C31-C
5-10 Troubleshooting Charts: Display Failure (NNTN4563, NNTN4819, & NNTN4717 VOCON Kits)
Display Failure (NNTN4563, NNTN4819, & NNTN4717 VOCON Kits)
Page 3
MAEPF-27507-A
Low-
Level Pulses
Present?
Check Active
Low Status on
both RESET
and CS
Use an oscilloscope to check for
a low-level (0V) pulse occurrence
during power-on initialization period.
Use an oscilloscope to check for
either a low-level (0V) pulse or
high-level (0-V2) occurrence during
power-on initialization period.
No
Ye s
No
Ye s
3
Signal
present
at appropriate
level?
Replace
Display
Check J301, pins
15 and 16 for
appropriate voltage
levels (0-V2)
Return radio to
service depot for
further analysis