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AE/LZB 119 1647 R1A
31
Symptom
Probable Cause
Corrective Action
Radio appears dead.
1. On/off switch is defective.
2. Power supply fuse (F101) is
defective.
3. Bad 5V regulator (U109,110,801)
4. DC Power problem.
1. Replace on/off switch.
2. Replace fuse.
3. Replace bad regulator.
4. Check PCB pattern or input power circuit. R170,
D106, etc.
LCD is blank with no
problems in the voltage
source.
1. Bad LCD driver chip (U103).
2. Radio operating code is corrupt.
3. CPU crystal oscillator problem.
4. CPU reset problem.
5. CPU problem.
1. Replace U103 or entire keypad board.
2. Re-flash radio.
3. Check that oscillator frequency is 11.0592 MHz
+/- 1000 Hz. If not replace X701.
4. Check that U801 pin 5 is +5Vdc. If not replace
U801.
5. Replace U701 or entire digital board..
“PRS ERR” is displayed on
LCD.
1. EEPROM (U104) memory is
corrupted.
1. Reprogram the radio’s personality. If problem
still persists replace U104.
“SYN LOC” is displayed on
LCD.
1. Problem in PLL network
including U106, C155, C156, etc.
2. Defective dc-dc converter
including U105, 108, D105, etc.
3. Defective TCXO.
4. Defective VCO.
5. Digital and RF board interconnect
problem.
1. Program a high and low frequency channel. If
either channel works the VCO may need adjusted.
Re-adjust TC301. If neither channel works do not
readjust TC301
2. Check for +8Vdc on pin 5 of U106. If it is not
there, problem is in converter.
3. Check TCXO oscillation frequency for 12.8
MHz.
4. Check for VCO power at VCO output terminal.
5. Be sure RF and digital boards are seated tightly
together.
When transmitting in talk-
around “SYN LOC” is
displayed on LCD.
1. Problem with Q107 which
controls voltage of VCO T/A pin.
1. Replace Q107 if necessary.
Low battery indicator with
fully charged battery.
1. Problem with voltage divider
R801 and R802.
2. Defective fuse (F101).
1. Replace R801 or R802.
2. Check F101 for resistance. If greater than 1.0
ohm replace fuse.
Low or no received audio
power at internal or
external speaker.
1. Mis-aligned quadrature detector
(L105).
2. Defective volume control knob
(RV103).
3. Defective audio amplifier (U603).
4. Defective internal/external
speaker switch (Q102).
5. Defective internal or external
speaker.
6. Defective audio signal processor
chip (U804).
1. Re-align L105 for proper audio output signal.
2. Check volume pot resistance. If greater than 20K
ohms replace volume knob.
3. If audio signal is present at pin 3 but not at pin 5
replace audio amp.
4. Replace Q102.
5. Check speaker resistance. If greater than 8 ohms
replace speaker.
6. Replace ASP or entire digital board.
Summary of Contents for EDACS Monogram Series
Page 1: ...ericssonz ericssonz Maintenance Manual MONOGRAM SERIES EDACS Trunking Portable 800 MHz ...
Page 45: ...AE LZB 119 1647 R1A 45 COMPONENT PINOUT 780 202 0009 Sh 1 Rev A ...
Page 46: ...AE LZB119 1647 R1A 46 COMPONENT PINOUT 780 202 0009 Sh 2 Rev A ...
Page 47: ...AE LZB 119 1647 R1A 47 SYSTEM WIRING DIAGRAM 930 010 0002 Rev A ...
Page 48: ...AE LZB119 1647 R1A SERVICE OUTLINE 48 KEYPAD DISPLAY BOARD 930 010 0002 Rev A ...
Page 49: ...SCHEMATIC DIAGRAM AE LZB 119 1647 R1A 49 PTT SWITCH BOARD 650 180 0001 S1800001 Rev A ...
Page 50: ...AE LZB119 1647 R1A SCHEMATIC DIAGRAM 50 KEYPAD DISPLAY BOARD 650 170 0001 S1700001 Rev A ...
Page 51: ...RF BOARD 650 020 0002 770 020 0002 Rev D AE LZB 119 1647 R1A 51 ...
Page 52: ...DIGITAL BOARD 650 010 0003 770 010 0003 Sh 1 Rev E AE LZB 119 1647 R1A 52 ...
Page 53: ...DIGITAL BOARD 650 010 0003 770 010 0003 Sh 2 Rev E AE LZB 119 1647 R1A 53 ...
Page 54: ...BLOCK DIAGRAM 060 010 0001 Rev B AE LZB 119 1647 R1A 54 ...
Page 55: ...This page intentionally left blank AE LZB 119 1647 R1A 55 ...