HP 8753E - Page 565

A21, A22 Test Port Couplers
Tools Required
n T-10 TORX screwdriver
n T-15 TORX screwdriver
n small slot screwdriver
n ESD (electrostatic discharge) grounding wrist strap
n 5/16-inch open-end torque wrench (set to 10 in-lb)
Removal
1. DiscOMeCt the power cord and remove the bottom cover (refer to “Covers”
in this chapter).
2. Disconnect the small bias wire from the test set interface board (A25).
For coupler A2 1 disconnect the gray wire (A2 1 W 1).
For coupler A22 disconnect the gray wire (A22Wl).
3. Disconnect the two semirigid cables from the coupler assembly.
For coupler A21 disconnect W3 and W31.
For coupler A22 disconnect W4 and W32.
4. Remove the four screws, washers, and pressure springs that secure the
coupler to the test set deck. Remove the coupler.
5. Remove the pressure springs
Replacement
1. Reverse the order of the removal procedure.
Note
n If you’re instalhng a new coupler, the gold lead on the
feedthru capacitor (item 1) must be curt@&@ bent at
90 degrees to prevent it from shorting to the bottom cover.
n When reconnecting semirigid cables, it is recommended that
the connections be torqued to 10 in-lb.
14-50 Assembly Replacement and Past-Repair Procedures