Maintenance
371B Service Manual
4-19
A16 HighĆCurrent Control Board.
Perform the following to remove the A16
High-Current Control board from the drawer unit.
1. Remove the drawer unit from the 371B.
2. Remove the shield (four screws) that covers the A31 Relay board and the
A16 High-Current Control board.
3. Remove J690, J906, J908, J912, and J914 from the A16 High-Current
Control board.
4. Remove the four screws that secure the A16 High-Current Control board to
the drawer unit chassis.
5. Lift the A16 High Current board from the drawer unit chassis.
6. Install the A16 High Current Control board in the reverse order of removal.
FETs Q910, Q920, Q930, and Q940.
These field effect transistors are chassis-
mounted under the A16 High Current Control board. Perform the following to
access and remove these transistors.
1. Remove the drawer unit from the 371B.
2. Remove the shield (four screws) that covers the A31 Relay board and the
A15 High Current Control board.
3. Remove the A16 High Current Control board as previously explained.
4. Remove the four spacer posts, using a 7/32 inch Spintite, that attach the
rectangular shield to the chassis standoffs.
5. Lift the electrical shield from the drawer unit.
6. Remove the eight 5/16 inch nuts that attach the FET assembly to the drawer
unit chassis.
7. Remove the yellow and black wires from the FET assembly.
8. Lift the FET assembly from the drawer unit.
9. Install the A16 High-Current Control board in the reverse order of removal.
Other Drawer Unit ChassisĆmounted SubĆassemblies and Components.
The drawer
unit contains several chassis-mounted subassemblies and components. Refer to
the “Drawer Chassis” drawing in Chapter 9: Mechanical Parts for location of
these subassemblies and components.
Summary of Contents for 371B
Page 4: ......
Page 14: ...Service Safety Summary 371B Service Manual...
Page 18: ...Preface 371B Service Manual...
Page 21: ...Specifications...
Page 22: ......
Page 24: ...Product Overview 371B Service Manual...
Page 38: ...Specifications 371B Service Manual...
Page 39: ...General Information...
Page 40: ......
Page 58: ...General Information 371B Service Manual...
Page 59: ...Theory of Operation...
Page 60: ......
Page 62: ...Theory of Operation 3 2 371B Service Manual Figure 3 1 371B Block Diagram...
Page 71: ...Maintenance...
Page 72: ......
Page 101: ...Performance Verification...
Page 102: ......
Page 220: ...Performance Verification 371B Service Manual...
Page 221: ...Options...
Page 222: ......
Page 226: ...Options and Accessories 371B Service Manual...
Page 227: ...Electrical Parts List...
Page 228: ......
Page 235: ...Diagrams...
Page 236: ......
Page 237: ...8 1 371B Service Manual Circuit Board Interconnections 2 2...
Page 238: ...371B Service Manual...
Page 239: ...8 3 371B Service Manual Circuit Board Interconnections 2 2...
Page 240: ...371B Service Manual...
Page 241: ...8 5 371B Service Manual Test Point Adjustment Locations 1...
Page 242: ...8 6 371B Service Manual Test Point Adjustment Locations 2...
Page 243: ...8 7 371B Service Manual Test Point Adjustment Locations 2...
Page 244: ...8 8 371B Service Manual Test Point Adjustment Locations 3...
Page 245: ...8 9 371B Service Manual Troubleshooting Tree...
Page 246: ...8 10 371B Service Manual Troubleshooting Tree Cont...
Page 247: ...8 11 371B Service Manual Troubleshooting Tree Cont...
Page 248: ...371B Service Manual...
Page 249: ...Mechanical Parts List...
Page 250: ......
Page 259: ...9 9 371B Service Manual Figure 9 1 Cabinet Rear 97 96 68...
Page 260: ...371B Service Manual...
Page 261: ...9 11 371B Service Manual Figure 9 2 Display Front 73...
Page 262: ...371B Service Manual...
Page 267: ...9 17 371B Service Manual Figure 9 3 Chassis Ciircuit Board...
Page 268: ...371B Service Manual...
Page 269: ...9 19 371B Service Manual Figure 9 4 Power Supply...
Page 270: ...371B Service Manual...
Page 276: ...Mechanical Parts List 371B Service Manual...
Page 277: ...9 27 371B Service Manual Figure 9 5 Test Fixture 78 78 REV MAR 96 75 72...
Page 278: ...371B Service Manual...
Page 279: ...9 29 371B Service Manual Figure 9 6 Front Porch...
Page 280: ...371B Service Manual...
Page 287: ...371B Service Manual...
Page 288: ...371B Service Manual...
Page 289: ...371B Service Manual 6 5...
Page 290: ...371B Service Manual...