Chapter 1 Introduction
1.1 General
This manual includes all the information needed to maintain peak product performance and 
maximum working-time. This detailed level of service (component level) is typical of some service 
centers, self-maintained customers, and distributors. This manual is to be used in conjunction with 
the ASTRO XTS 2500/XTS 2500
I/XTS 2000/ATS 3000 Digital Portable Radios Basic Service 
Manual (Motorola part number 6816984H01), which uses the pass/fail service approach to radio 
problems.
Conduct the basic performance checks first. This will verify the actual need for analyzing the radio 
and help pinpoint the functional problem area. In addition, the technician will become familiar with 
the radio test mode of operation, which is a helpful tool. If any basic receive or transmitter 
parameters fail, then the radio should be aligned per the radio alignment procedure.
Included in other areas of this manual are disassembly/reassembly procedures, functional block 
diagrams, detailed theory of operation, troubleshooting charts and waveforms, schematics and parts 
lists, and exploded view and parts list. The technician should be very familiar with these sections to 
aid in determining the problem circuit. Also included are component location diagrams to aid in 
locating individual circuit components and some IC diagrams, which point out some convenient 
probe points.
The theory of operation sections of this manual contain detailed descriptions of the operations of 
many circuits. Once the area of the problem is located, it would be strongly advisable to review the 
operation of the circuit pertaining to the troubleshooting flow chart.
1.2 Notations Used in This Manual
Throughout the text in this publication, you will notice the use of warning, caution, and note 
notations. These notations are used to emphasize that safety hazards exist, and care must be taken 
and observed.
NOTE: An operational procedure, practice, or condition, etc., which is essential to 
emphasize.
!
Caution
CAUTION indicates a potentially hazardous 
situation which, if not avoided, may
 result in 
equipment damage.
!
WARNING
!
WARNING indicates a potentially hazardous 
situation which, if not avoided, could
 result in 
death or injury.