Motorola Astro Digital Mobile Radio Xtl5000 Detailled 6881096c74 B Manual

							Chapter 1 Introduction
1.1 Notations Used in This Manual
Throughout the text in this publication, you will notice the use of warnings, cautions, and notes. 
These notations are used to emphasize that safety hazards exist, and care must be taken and 
observed.
NOTE:The Note notation indicates an operational procedure, practice, or condition that is essential 
to emphasize.
1.2 General
This manual includes all the information necessary 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.
Use this manual in conjunction with the ASTRO Digital XTL 5000 VHF/UHF Range 1/UHF Range 2/
700–800 MHz Mobile Radio Basic Service Manual (Motorola part number 6881096C73), which helps 
in troubleshooting a problem to a particular board.
Conduct the basic performance checks first to verify the need to analyze the radio and help pinpoint 
the functional problem area. In addition, you will become familiar with the radio test mode of 
operation which is a helpful tool. If any basic receiver or transmitter parameters fail to be met, the 
radio should be aligned using the radio alignment procedure described in the ASTRO Digital 
XTL 5000 VHF/UHF Range 1/UHF Range 2/700–800 MHz Mobile Radio Basic Service Manual. CAUTION indicates a potentially hazardous situation which, if 
not avoided, might
 result in equipment damage.
WARNING indicates a potentially hazardous situation 
which, if not avoided, could
 result in death or injury.
DANGER indicates an imminently hazardous 
situation which, if not avoided, will
 result in death or 
injury.
!
C a u t i o n
D A N G E R
! 
						

							May 25, 20056881096C74-B
1-2Introduction: General
Included in other areas of this manual are functional block diagrams, detailed theory of operation, 
troubleshooting charts and waveforms, schematics, and parts list. You should be familiar with these 
sections to aid in deducing the problem circuit. Also included are component location diagrams to aid 
in locating individual circuit components, as well as IC diagrams, which identify some convenient 
probe points.
The Theory of Operation section of this manual contains detailed descriptions of operations of many 
circuits. Once you locate the problem area, review the Troubleshooting Chart for that circuit to fix the 
problem. 
						

							Chapter 2 Product Overview
2.1 Introduction
The ASTRO Digital XTL 5000 radio is a dual-mode (trunked/conventional), microcontroller-based 
transceiver incorporating a Digital Signal Processor (DSP). The microcontroller handles the general 
radio control, monitors status, and processes commands input from the keypad or other user 
controls. The DSP processes the typical analog signals and generates the standard signaling 
digitally to provide compatibility with existing analog systems. In addition it provides for digital 
modulation techniques utilizing voice encoding techniques with error correction schemes to provide 
the user with enhanced range and audio quality all in a reduced bandwidth channel requirement. It 
allows embedded signaling which can mix system information and data with digital voice to add the 
capability of supporting a multitude of system features.
The XTL 5000 radios are wideband, synthesized, fixed-tuned radios and are available in the VHF 
(136–174 MHz), UHF Range 1 (380–470 MHz), UHF Range 2 (450–520 MHz), 700 MHz, and 
800 MHz bands. All XTL 5000 radios are capable of both analog operation (12.5 kHz, 20 kHz, and 
25 kHz bandwidths) and ASTRO mode operation (12.5 kHz bandwidth).
NOTE:The UHF radio does not support 20 kHz bandwidth.
2.2 Functional Blocks
The XTL 5000 radios contain the following functional blocks:
• Control-Head Assembly (Dash- or Remote-Mount)—is connected directly to the front of the 
transceiver or remotely by the interconnect board and control cable. This assembly contains a 
vacuum fluorescent (VF) display, VF driver, microprocessor and serial bus interface.
• Radio Power Distribution—contains voltage-regulation circuitry for power distribution 
throughout the radio.
• Receiver Front-End section—contains the preselector, low-noise amplifier (LNA), and mixer.
• Receiver Back-End section—contains the receiver intermediate-frequency (IF) amplifier/filter 
and the digital receiver back-end integrated circuit (IC).
• Transmitter section—contains the antenna switch, directional coupler/ detector, and power 
amplifier circuitry.
• Frequency Generation section—contains the synthesizer, voltage controlled oscillators (VCOs), 
reference oscillator, and receive and transmit buffers.
• Controller section—combines a vocoder and a controller into a single section containing the 
following elements:  
						

							May 25, 20056881096C74-B
2-2Product Overview: Control-Head Assembly
2.3 Control-Head Assembly
This section discusses the basic operation and components of each control-head assembly.
2.3.1 Display, Vacuum Fluorescent Display Driver, Vacuum Fluorescent Voltage 
Source, Controls and Indicators, Status LEDs and Backlight LEDs
For information on the above, please refer to: 
• W3 Control Head User’s Guide, 6881096C67 and 
• W4, W5, W7 and W9 Control Heads User’s Guide, 6881096C68.
2.3.2 Vehicle Interface Ports
The Vehicle Interface Ports (VIPs) allow the control head to activate external circuits and receive 
inputs from the outside world. In general, VIP outputs are used for relay control, and VIP inputs 
accept inputs from external switches. The VIP IN and VIP OUT lines move as the configuration 
changes from Dash, to Remote, to Remote plus DEK. See the cable kit section for typical 
connections of VIP input switches and VIP output relays.
2.3.2.1  Dash-Mount Control-Head Configuration (Mid Power Only)
In the dash-mount configuration (Figure 2-1), only two VIP output pins are available, and they are 
located at the 26-pin accessory connector, J2-18 and J2-19. VIP input lines are not available in this 
configuration.
Figure 2-1.  VIP Dash-Mount Configuration
2.3.2.2  Remote-Mount Standard Control-Head Configuration
Once the radio is put into a remote-mount configuration (Figure 2-2 on page 2-3), the two VIP output 
pins located at the rear connector (J2) stop functioning, and the VIP output pins located on the back 
of the control head below the area labeled VIP become the new VIP output pins. These 
connections are used to control relays, just as in the dash-mount configuration. One end of the relay 
should be connected to SWB+, while the other side is connected to VIP IN or VIP OUT pins (these 
pins are software-controlled on/off switches via transistors inside the control head or on the 
interconnect board).
Pin 18
Pin 19Pin 11
Pin 12Pin 18
Pin 19VIP OUT 1
VIP OUT 2
Control
HeadMain Board
(Radio)
U1
MC68HC
MAEPF-27921-O
No connect
Microprocessor SIOICSB9600 data
lines toggle
VIP-OUT
hadware
inside the
Control Head 
						

							6881096C74-BMay 25, 2005
Product Overview: Control-Head Assembly2-3
Figure 2-2.  VIP Remote-Mount Configuration
Figure 2-3.  VIP Remote-Mount Pin-Outs (Male)
Control
HeadMain Board
(Radio)
U1
MC68HC
MAEPF-27922-O
Microprocessor SIOICSB9600 data
lines toggle
VIP-OUT
hadware
inside the
Control Head
VIP OUT 1
VIP OUT 2
1           2          3          4           5                       7          8                      10        11         12        13         14        15         16         17
18         19         20        21                  23         24                     26        27         28        29         30        31         32        33
34           35         36     37         38                    40         41                     43        44         45        46        47         48        49         50
SWB  SWB  GND  GND
MIC VIP RADIO1 1 VIP OUT VIP IN2 2 VIP OUT VIP IN
+
 SWB  GND                                                        
++
MAEPF-27918-O 
						

							May 25, 20056881096C74-B
2-4Product Overview: Control-Head Assembly
2.3.2.3  Remote-Mount W3 Hand-Held Control Head Configuration
Because the W3 control head does not have an interface for VIPs on the control head itself, the radio 
and the W3 interconnect board must work together to provide VIP OUT at the back of the radio 
(Figure 2-4). The driving transistors (for the ON/OFF relay control) are located on the W3 
interconnect board. Therefore, the microprocessor on the main board uses one set of lines to 
interface with the interconnect boards transistors and a second set of return lines, which travel back 
to the main board and pass through to the back of the radio. Also, by using a Y-split cable HKN6096, 
VIP OUT also can be accessed at its 15-pin connector. However, the voltage levels are slightly lower 
since the VIP SWB+ of the interconnect board is different from the SWB+ of the radio.
Figure 2-4.  VIP Remote-Mount W3 Control-Head Configuration
2.3.2.4  Remote-Mount plus DEK Configuration
Another remote-mount configuration possibility is the addition of up to three Direct Entry Keypad 
(DEK) boxes (Figure 2-5 on page 2-5). A DEK is an accessory that is used with a mobile radio to 
provide extra buttons, indicators, and VIPs to the user. Just as the VIP output pins moved from the 
rear of the radio to the rear of the control head, the VIP pins also move from the back of the control 
head to the back of the DEK. The benefit of using a DEK box is that you gain three additional 
VIP OUT and VIP IN pins for each DEK added. The first DEK box provides the original three 
VIP OUT and three VIP IN pins. The next DEK provides an additional three VIP OUT and three 
VIP IN pins. A final DEK box provides an additional three VIP OUT and three VIP IN pins for a total 
of nine VIP OUT and nine VIP IN pins.
Pin 16
Pin 17
Pin 16
Pin 17Pin 14
Pin 27
Pin 18
Pin 17Pin 13
Pin 14
Pin 11
Pin 12Pin 18
Pin 19VIP OUT 1 Micro-
processor
VIP OUT 2 JU512
JU513
W3 Remote
Interconnect
BoardMain Board
(Radio)
MAEPF-27923-O 
						

							6881096C74-BMay 25, 2005
Product Overview: Control-Head Assembly2-5
Figure 2-5.  VIP Remote-Mount Plus DEK Configuration
Figure 2-6.  VIP Remote-Mount Plus DEK Pin-Outs (Male)
Kit HKN4273 contains:
- One DEK-to-DEK interface cable (A)
- One 24-pin DEK VIP connector (B)
- One 14-pin non-DEK VIP connector
- Forty cimping pins(A) DEK interface lines:
DATA IN
DATA OUT
STROBE
CLOCK When a DEK is added, the
radio VIPs move from J2
and from the back of the
control head to the back of
the DEK.
Main Board
(Radio)
Control Head
(W4, W5, W7, W9)
DEK A
DEK B
DEK C
SB9600 bus
messaging
interface
3 VIP - INs
3 VIP - OUTs 3 VIP - INs
3 VIP - OUTs
3 VIP - INs
3 VIP - OUTs
MAEPF-27925-O
(B)
1           2          3          4           5                       7          8                      10        11         12        13         14        15         16         17
18         19        20         21                     23        24                     26        27         28        29         30        31         32        33
34        35         36        37         38                    40         41                     43        44         45        46        47         48        49         50
STROBE       GND         CLOCK        DATA                 VIP OUT    VIP OUT                          SWB+
SWB+           DATA                            SWB+               VIP OUT                          SWB+        SWB+OUT
IN1
3 OUT            STROBE                                                                       2
GND                    GND           GND
3
2
FROM
CONTROL HEAD
OR PREVIOUS DEK BOX TO NEXT DEK BOX DEK VIP-INs AND VIP-OUTsINGND CLOCKDATA                                                      VIP IN        VIP IN D ATA
VIP IN
MAEPF-27917-O
1 
						

							May 25, 20056881096C74-B
2-6Product Overview: Control-Head Assembly
2.3.2.5  VIP Output Connections:
There are three VIP outputs that are used for the W9 control head and two VIP outputs for the W3, 
W4, W5, and W7 control heads. The VIP outputs are normally at SWB+ levels and are driven low by 
logic within the control head for both the dash- and remote-mount configurations. Field programming 
of the radio can define the functions of these pins. The output transistors that drive the VIP outputs 
can sink 300 mA of current and are primarily used to control external relays. These relays should be 
connected between the respective VIP output pin and switched B+.
VIP outputs are controlled by SB9600 Update_Indicator messages. Therefore, multiple indicators 
and their status information can be sent with a single message.
The relay can be normally ON or normally OFF depending on the configuration of the VIP outputs. 
The CPS can be used to program the function of these VIP outputs in the radio.
The following are typical applications currently supported with ASTRO products:
• Horn relay
• Light relay
• Siren horn transfer
2.3.2.6  VIP Input Connections:
There are three VIP inputs that accept inputs from switches. VIP input messages are sent via the 
SB9600 pins as SB9600 BUTCTL messages. One side of the switch connects to ground while the 
other side connects to a buffered input to the control head. The switch can be normally closed or 
normally open depending on the configuration of the VIP inputs. The CPS can be used to program 
the function of these VIP inputs in the radio.
The following are typical applications currently supported in ASTRO products:
• Siren horn ring
• Auxiliary siren
For the remote configuration of W4, 5, 7 and 9 control heads, refer to sections 3.1.2 and 3.2.1 of the 
Installation Manual, 6881096C72.Table 2-1.  Control-Head VIP Locations
Ty p eConfigur
-ationPower 
LevelVIP LocationNumber of 
VIP InputsNumber of 
VIP Outputs
W3 Remote Midpower J3-3 and J3-12
Remote Mount Accessory Cable 
HKN6096None 2
W3 Dash Midpower J2-18 and J2-19
Rear Accessory ConnectorNone 2
W4 Dash Midpower J2-18 and J2-19
Rear Accessory ConnectorNone 2
W5 Dash Midpower J2-18 and J2-19
Rear Accessory ConnectorNone 2
W7 Dash Midpower J2-18 and J2-19
Rear Accessory ConnectorNone 2 
						

							6881096C74-BMay 25, 2005
Product Overview: Control-Head Assembly2-7
2.3.2.7  DEK Interface With Radio: Remote-Mount (W4, W5, W7, W9)
A maximum of three DEKs can be daisy chained to a single mobile radio. DEKs are only used with 
the W4, W5, W7, and W9 control heads when they are remotely mounted on the radio. DEKs are not 
used with any dash-mount control heads, including W4, W5, W7, or W9. The W3 control head does 
not support DEK, except in a special siren cabling configuration where the DEK 6-pin cable splits off 
the SIREN cable and plugs into the back of a DEK box.
The VIP lines in the control head are used to connect a DEK. There are four lines that are needed to 
communicate with the DEK: DATA IN, DATA OUT, STROBE, and CLOCK. These lines are shared 
with the VIP lines in the control head (see Table 2-1 on page 2-6) and, as a result, the control head 
loses its VIP lines when connected to a DEK. However, each DEK has its own VIP lines (three 
VIP IN and three VIP OUT lines) that can be used.
Each DEK box is essentially a shift register consisting of eight buttons/indicators together with the 
VIP lines. A raw, 48-bit stream of data from the control head is clocked into the first DEK box that is 
directly connected to it. This DEK box only shifts the bits forward to DEK B, which, in turn, forwards 
the bits to DEK C. Thus, bit 0 leaving the control head is actually stored as the last bit of DEK C. The 
full 48 bits is always clocked in/out regardless of the number of DEKs connected. The software is 
able to determine how many DEKs are actually connected by checking the DEK present bit for 
each DEK. The VIPs provided by each DEK box can then be used for driving external circuitry.
2.3.2.7.1  DATA IN
DATA IN consists of data entering from either the control head or another DEK. DATA IN is a raw bit 
stream fed into the DEK, which, in turn, essentially being a shift register, moves the data forward to 
the next DEK. DATA IN is a 48-bit stream that consists of indicator data (0 = off, 1 = illuminated) and 
VIP output data.
2.3.2.7.2  DATA OUT
DATA OUT consists of data leaving the DEK and either entering a control head or another DEK. 
DATA OUT is a 48-bit stream that consists of button data (0 = pressed, 1 = released), VIP input data, 
and DEK present.
2.3.2.7.3  STROBE
The STROBE line is used to latch the data contained in the shift registers inside the DEK box. This 
line is used to inform the DEK that the data contained in its shift registers is now valid.
2.3.2.7.4  CLOCK
The CLOCK line is used to shift data in and out through the shift registers located in the DEK boxes.
2.3.3 Power Supplies
The +5-V supply is a three-terminal regulator IC to regulate the 12 V SWB+ down for the digital logic 
hardware.
2.3.4 Ignition Sense Circuits
A transistor senses the vehicle ignition’s state, disabling the radio when the ignition is off. For 
negative-ground systems, the orange lead is typically connected to the fuse box (+12 V). 
						

							May 25, 20056881096C74-B
2-8Product Overview: Receiver Section
2.4 Receiver Section
This section discusses the receiver section components and basic operation for each band.
2.4.1 VHF Band Radios
The VHF (136–174 MHz) receiver consists of a front-end and a back-end sections.
2.4.1.1  Front-End Section
The primary function of the receiver front-end is to optimize image rejection and selectivity while 
providing the first conversion. The front-end uses discreet filters and LNAs. The first filter reduces 
the IF spur, image frequency response and limits some of the out-of-band interference. The second 
filter following the second low-noise amplifier (LNA) provides additional image rejection and half IF 
spur.
The receiver front-end signal is fed to the monolithic mixer IC where it is down converted to an IF of 
109.65 MHz. The mixer is driven by the receiver injection buffer that provides 20 dBm to the mixer. 
The VCO performs high side injection for the VHF band. The design maintains temperature stability, 
low insertion loss, and high out-of-band rejection.
2.4.1.2  Back-End Section
The crystal filters provide IF selectivity and out-of-band signal protection to the back-end IC. Two 2-
pole crystal filters centered at 109.65 MHz that are isolated from one another by a stable, high-gain 
low noise amplifier are used to meet the receiver specifications for gain, close-in intermodulation 
rejection, adjacent-channel selectivity, and second-image rejection.
The output of the IF circuit is fed directly to the Abacus III digital back-end IC. The ABACUS III is an 
IC with a variable-bandwidth bandpass Sigma-Delta architecture. It is capable of down-converting 
analog, as well as digital, RF protocols into a baseband signal transmitted on the Synchronous Serial 
Interface (SSI) bus. The ABACUS III IC converts the 109.65 MHz signal from the IF section down to 
2.25 MHz using a second LO frequency of 107.4 MHz or 111.9 MHz. The second LO VCO is tuned to 
107.4 MHz (low side), but can be modified to 75.6 MHz (high side injection) depends on known 
spurious interference related to the programmed received frequency.
2.4.2 UHF Range 1/UHF Range 2 Band Radios
The UHF Range 1 (380–470 MHz)/UHF Range 2 (450–520 MHz) receiver consists of a front-end 
section and a back-end section.
2.4.2.1  Front-End Section
The receiver front-end consists of a switchable high pass filter and LNA, a preselector, a switchable 
attenuator, a second switchable low noise amplifier (always in for UHF Range 2), image filter, mixer, 
and injection amplifier. The preselector filter is varactor-tuned and is aligned at the factory. The radio 
tuner software can also be used to check and re-align the preselector. The switchable stage provides 
AGC capability.
The signal from the preselector is amplified by the low noise amplifier, then filtered by the image filter 
before it is sent to the mixer. The mixer uses the LO signal, amplified by the injection amplifier, to 
convert the RF signal to IF frequency of 109.65 MHz. This signal is then sent to the IF and back-end 
circuits.
2.4.2.2  Intermediate Frequency and Back-End
The Intermediate Frequency (IF) consists of a crystal filter, amplifier, a second crystal filter, and a 
switchable attenuator. This provides selectivity at the IF while attenuating out-of-band signals and 
protecting the back-end (BE) IC.