Instruction manual

6881086C22-B 57
Trunking Tones Not Heard at Remote Console Troubleshooting Chart
Check/replace
microprocessor.
No
Is a
0-5VDC signal
present at
U123-38?
Are
associating
trunking tones heard at
the local consolette
speaker?
Is the
local speaker
connected?
Check/replace
U106.
Yes
Do the
trunking tones
appear at
R171?
Monitor U123-38
during the time when
trunking tones should
be present
(on each push-to-talk).
Apply a Push-to-Talk
to the consolette
on a trunking
channel.
Yes
Yes
Yes
Check VB, 9.6V and
FILTER_CLOCK signal,
also, be certain HY2
is inserted properly.
No
Does the
signal appear
at U114-13?
Check for
proper operation
of U124.
Yes
No
No
Does the
signal appear
at U114-14?
No
Do the
trunking tones
appear at line 1
output?
Yes
Determine why
U123 is holding
signal low and
repair.
No
Does the
signal appear at
line 1 output?
Yes
Check 9.6V and VB,
also, evaluate
operation of U111 and
position of R545 wiper.
Check HY2 for
correct operation and
replace if necessary.
Is
WL_MUTE signal
high?
Check/replace
U113 and U114.
No
Does the
signal appear
at TP3?
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
Refer to TRC
Board Voltage
Troubleshooting
Chart.
No
Is
9.6V and VB
present?
Check for
correct operation
of U127 and U123.
No
Is
filter_clk signal
a 0-5V square wave
at 110.4kHz?
4
4
1
2
3
2
5
6
6
6
3
3
4
5
6
Check/replace
transformer.
No
Is
signal at
secondary of
T100?
Yes
Check 9.6V and VB;
also, check for
correct operation
of U111.
Check/replace
Q114 and/or
Q115.
No
Is
signal at
U111-1?
Yes
TRUNKING/MDC TONES NOT HEARD
AT REMOTE CONSOLE
STOP
MAEPF-26159-O
Check the
programming of the
trunking channel in the
consoletteÕs codeplug.
1
Connect the
speaker.
1
Is S100-2
set to OFF?
Set S100
correctly
START
START
START
STOP