User's Manual Part 2
Table Of Contents
- Maintenance
- Introduction
- Scheduled Maintenance
- Unscheduled Maintenance
- Introduction
- Tools, Materials and Test Equipment Required
- T6T VHF Amplifier Procedures
- Top and Bottom Covers
- Removing and Refitting the Interface Module
- Removing and Refitting the PSU Regulation Module
- Removing and Refitting the Power Supply Modules
- Removing and Refitting the Combiner BIT Module
- Removing and Refitting the PA Modules
- Removing and Refitting the Front Panel PCB
- Removing and Refitting the Cooling Fans
- T6T VHF Drive Assembly Procedures
- Removing the Top Cover
- Removing and Refitting the Processor Module
- Removing and Refitting the PSU Regulation Module
- Removing and Refitting the Drive Module
- Removing the Bottom Cover
- Removing and Refitting the PA Control Module
- Removing and Refitting the Power Supply
- Removing and Refitting the Front Panel PCB
- Virtual Front Panel (VFP)
T6T 300 Watt VHF Transmitter Page 123 Maintenance
Removing and Refitting the Power Supply
The Power Supply is located as shown in Fig 44. A module removal diagram is shown in Fig 50.
Dangerous voltage is present within the drive assembly. Care must be taken by personnel to
avoid accidental contact with exposed circuitry when the covers are removed and power is
applied to the radio.
Removal
Before attempting to remove the Power Supply, ensure that the drive assembly is isolated from the ac
and dc input supplies. Disconnect the six Amplifier Out connectors, CN1 to CN6. Then proceed as
follows:
(1) Remove the drive assembly top and bottom covers as described on page 116 and page 121.
(2) Support the drive assembly on its side.
(3) Locate the power supply. From the bottom half of the unit remove the four No. 6 x 32 UNC
countersunk screws that secure the power supply to the drive assembly mainframe. During this
operation support the power supply from the top half of the unit.
(4) Withdraw the power supply from the chassis sufficient to allow access to the power terminal
blocks taking care not to damage the ac terminal plastic supply guard.
(5) Remove the connector CN4 (power supply to the PSU regulation module CN6).
(6) Disconnect the dc wires from the eight connector terminal block.
(7) Slide back the terminal block cover and disconnect the ac wires from the three connector terminal
block (marked L N E).
(8) Carefully remove the power supply from the drive assembly.
Refitting
To refit the Power Supply:
(1) With the drive assembly on its side hold the power supply near to its securing position in the top
half of the radio.
(2) Slide back the terminal block cover and connect the ac wires to the three connector terminal
block (marked L N E); brown to terminal L, blue to terminal N and yellow/green to terminal E.
(3) Connect the dc wires to the eight connector terminal block; red to terminal 2 and terminal 3 and
black to terminal 6 and terminal 7.
(4) Connect CN4.
(5) Taking care not to damage the plastic supply guard, lower the power supply into position and
secure from the bottom half of the unit using the four countersunk screws previously removed.
(6) Re-connect the six Amplifier Out connectors, CN1 to CN6.
(7) Re-establish the ac and/or dc supplies.
(8) Switch power on using the rear mounted Supply switch.
(9) Ensure the front panel Ready indicator is lit and the Alarm indicator is unlit.
(10) Carry out a BIT interruptive test as detailed in the procedure To Initiate a BIT Test on page 102.
WARNING Dangerous Voltage