Tektronix 371B Service Manual page 91

371B Service Manual
A16 High Current 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 Chassis mounted Sub assemblies 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.
Maintenance
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