Motorola ASTRO Digital Spectra, Подробное руководство по обслуживанию

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September 5, 2008 6881076C25-E
4-2 Troubleshooting Procedures : ASTRO Spectra Procedures
4.1.2 Voltage Measurement and Signal Tracing
In most situations, the problem circuit may be identified using a dc voltmeter, RF millivoltmeter, and
oscilloscope (preferably with 100 MHz bandwidth or more). The “Recommended Test Equipment,
Service Aids, and Tools” section in the
ASTRO Digital Spectra and Digital Spectra Plus Mobile
Radios Basic Service Manual (6881076C20) outlines the recommended tools and service aids which
would be useful. Of special note are:
• 30-80370E06 Extender Cable which provides an extension cable for VOCON board connector
J501 and command board connector P501.
• RPX-4725A Command and Control Service Cable Kit which provides extension cables for
servicing digital and analog circuits.
• RPX-4724A RF Service Cable Kit which provides interface cables needed to service the RF
boards.
In some cases dc voltages at probe points are shown in red on the schematics. In other areas
diagrams are included to show time-varying signals, which should be present under the indicated
circumstances. It is recommended that a thorough check be made prior to replacement of any IC or
part. If the probe point does not have a signal reasonably close to the indicated one, a check of the
surrounding components should be made prior to replacing any parts.
4.1.3 Power-Up Self-Check Errors
Each time the radio is turned on the MCU and DSP perform some internal diagnostics. These
diagnostics consist of checking the programmable devices such as the FLASH ROMs, internal and
external EEPROMs, SRAM devices, and ADSIC configuration bus checksum. At the end of the
power-up self-check routines, if an error exists, the appropriate error code is shown on the display.
Self-test errors are classified as either “fatal” or “non-fatal.” Fatal errors will inhibit user operation;
non-fatal errors will not. For non-display radios, the error codes may be read using the Radio Service
Software (RSS) from the SB9600 bus on the universal connector.
Table 4-1 lists self-check error
codes, describes the codes, and recommends troubleshooting charts for investigating the cause of
the failure.
When checking a transistor or module, either in or out of
circuit, do not use an ohmmeter having more than 1.5 Vdc
appearing across test leads or use an ohms scale of less than
x100.
Table 4-1. Power-Up Self-Check Error Codes
Error
Code
Description Troubleshooting Chart
01/02 External EEPROM checksum non-fatal error Chart C.2
(p. 5-4)
, C.7
(p. 5-8)
01/81 ROM checksum failure Chart C.6
(p. 5-7)
01/82 External EEPROM checksum failure Chart C.2
(p. 5-4)
, C.7
(p. 5-8)
01/84 EEPROM is blank Chart C.2
(p. 5-4)
, C.8
(p. 5-8)
01/88 RAM failure - Note: Not a checksum failure Chart C.2
(p. 5-4)
, C.9
(p. 5-9)
01/90 General hardware failure Chart C.2
(p. 5-4)
, C.5
(p. 5-7)
01/92 Internal EEPROM checksum failure Chart C.10
(p. 5-9)
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C a u t i o n