266 E8257D/67D, E8663D PSG Signal Generators Service GuideAssembly ReplacementA1 KeyboardA1 KeyboardTools Required— T–10 driverRemoval ProcedureRefer to Figure 3-5 for instruments with serial number prefix< US/MY5XXX3XXX for this procedure.Refer to Figure 3-6 for instruments with serial number prefix≥ US/MY5XXX3XXX for this procedure.1. Disconnect the power cord.2. Remove the front panel. Refer to “Front Panel” on page 262.3. For serial number prefix < US/MY5XXX3XXX, disconnect the A2DS1W1cable from the A4 Inverter.For serial number prefix ≥ US/MY5XXX3XXX, disconnect the A2W1 cablefrom the A2 Display.4. Disconnect the W8 ribbon cable from the A3 Power Switch by lifting thewhite tabs on the connector.5. Using the T–10 driver, remove the four screws (12) from the A3 PowerSwitch.6. Remove the A3 Power Switch.7. Using the T–10 driver, remove the ten screws (11) that secure the RFIshielding (10) to the front panel.8. Remove the metal shielding.9. Using the T–10 driver, remove the four screws (9) that secure the A2Display to the front panel.10.Remove the A2 Display.11.Using the T–10 driver, remove the nine screws (8) that secure the A1Keyboard to the front panel.12.Remove the A1 Keyboard.Replacement Procedure1. Reverse the order of the removal procedures.2. Torque all T–10 screws to 9 in–lbs.3. Perform the post–repair adjustments and performance tests that pertainto this removal procedure.
