Receiver Front-End (Rxfe); Vhf (136-174 Mhz) Band; Uhf Range 1 (380-470 Mhz) Band; Table 4-21. Standard Operating Bias: Vip Lines (W3 Remote Configuration) - Motorola ASTRO Digital XTL 5000 Detailed Service Manual

Troubleshooting Procedures: Receiver Front-End (RXFE)

Table 4-21. Standard Operating Bias: VIP Lines (W3 Remote Configuration)

Nominal Value
NA
NA
SW_B+ level
0.3 V to 0.5 V
SW_B+ level
0.3 V to 0.5 V
Note: When using the W3 control head and interconnect board, the main board VIP_OUT lines are
pass-through-only lines.

4.11 Receiver Front-End (RXFE)

This section provides band-specific troubleshooting procedures for the receiver front-end.
4.11.1 VHF (136–174 MHz) Band
Use this information, along with the theory of operation, to diagnose and isolate the cause of failures.
The principle tools needed to troubleshoot a circuit to the component level are the schematic and the
theory of operation.
In addition to the schematic and theory, you can use the troubleshooting flowcharts in
Troubleshooting Charts"
isolate problems.
Prior to troubleshooting, it is important to review the theory of operation including specific
precautions and troubleshooting methods. Because much of the radio's circuitry operates at a high
frequency, measurements must be taken carefully.
4.11.2 UHF Range 1 (380–470 MHz) Band
Use this information, along with the theory of operation, to diagnose and isolate the cause of failures.
The principle tools needed to troubleshoot a circuit to the component level are the schematic and the
theory of operation.
In addition to the schematic and theory, you can use the troubleshooting flowcharts in
Troubleshooting Charts"
isolate problems.
Prior to troubleshooting, it is important to review the theory of operation including specific
precautions and troubleshooting methods. Because much of the radio's circuitry operates at
400 MHz, measurements must be taken carefully.
6881096C74-B
Signal Name
VIP_OUT_1_5v
VIP_OUT_2_5v
VIP_IN_1_5v
VIP_IN_2_5v
VIP_OUT_1_12v
VIP_OUT_2_12v
that will guide you through a sequence of tests and checks designed to
that will guide you through a sequence of tests and checks designed to
Range/State
Access only by custom
pin-out
Access only by custom
pin-out
Not supported with W3
Not supported with W3
Deactivate = relay
closed
Activate = relay open
Deactivate = relay
closed
Activate = relay open
Probe Locations
J0401-13
J0401-14
J0401-15
J0401-16
J0401-11, J2-18
J0401-12, J2-19
"Chapter 5.
"Chapter 5.
May 25, 2005
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