Specifications

59
START
WAS POWER_ON
INDICATION LIGHT
EMITTED?
YES
NO
APPLY POWER
TO RADIO
IS POWER
SUPPLIED TO DC-
DC CONVERTER?
WAS
NO WARNING LED
INDICATION?
YES
IS THERE
CONTINUOUS LED
FLASH?
CHECK
EEPROM DATA
IS EEPROM DATA
NO PROBLEM?
DONE
REPROGRAM EEPROM
& CHECK AGAIN
BUT, IF HAVE SAME
PROBLEM REPLACE
EEPROM (IC402)
TROUBLESHOOT FREQUENCY
SYNTHESIZER CIRCUITRY
(INCLUDES VCO & TCXO)
YELLOW
LED FLASH
GREEN LED
FLASH
CHECK EEPROM DATA
FOR MODEM OPTION &
TYPE OF INSTALLED
MODEM
(ACC-513 OR ACC514 ?)
NO
IS
CONTACT OF
18PIN INTERNAL
CONNECTOR
BETWEEN RF AND
DIGITA B'D
OK?
CHECK CONTACT OF
POWER CONNECTOR AND
RUNNERS BETWEEN
POWER CONNECTOR & DC-
DC CONVERTER
REASSEMBLE RF &
DIGITAL B'D AND
CHECK AGAIN. BUT, IF
HAVE SAME PROBLEM
REPLACE CONNECTOR
(CON405)
IS VCC AT CON405
PINS 1 & 16 OK?
TROUBLESHOOT
DC-DC CONVERTER
+5V AT
CON405
PIN 15?
TROUBLESHOOT
5V REGULATOR
CIRCUITRY OF RF B'D
WITH POWER SUPPLIED TO RADIO CHECK THE
FOLLOWING:
1) 5V AT THE PINS 39 & 40 OF IC401. IF NONE,
CHECK L401, C465 & C477.
2) WITH HIGH IMPEDENCE PROBE CHECK FOR
8.0MHZ AT PINS 2 & 3 OF IC401. IF NO SIGNAL
CHECK IC401 / X401 / R456 / C441 / C442.
3) CHECK DC AT PIN 4 OF IC401. IF < 4.5VDC,
CHECK RESET CIRCUITRY
(IC414 / R457 / R458 / C443)
4) CHECK FOR TYPICAL VOLTAGES OF IC401
IS
LED CONTROL
SIGNAL PRESENT
ON POWER UP AT
IC401 PINS
23 & 24?
CHECK LED401 AND
ITS DRIVERS
(Q401, Q411)
DONE
IS CORRECT
MODEM
INSTALLED?
IS
CONTACT
BETWEEN MODEM
AND DIGITAL B'D
OK?
TROUBLESHOOT OR
REPLACE MODEM
CHANGE MODEM
REINSTALL MODEM TO
DIGITAL B'D AND
CHECK AGAIN. BUT, IF
HAVE SAME PROBLEM
REPLACE CONNECTOR
(CON403)
YES
YES
YES
NO
NO
NO
NO
NO
YES
YES
NO
YES
YES
NO
NO
YES
Figure 9.6. Troubleshooting Flow Chart for Control Circuit