190 Chapter 8
Hardware Options
Overview and Verification of Option 123, Microwave and Millimeter Preselector Bypass
Figure 8-10 Option 123 Switch Wiring
Switches are actuated using a pulse drive. The pulse duration must be
at least 15 ms to ensure that the switch will fully latch.
The blue and brown wires provide the pulse drive to the switch.
Wire Color Voltage
Blue 25 Vdc, Steady state.
Preselector Off to On transition should show a
negative-going pulse for approximately 18 ms, then the
25 Vdc steady state
Green 25 Vdc supply
Yellow 25 Vdc supply
Brown 25 Vdc, Steady state.
Preselector On to Off transition should show a
negative-going pulse for approximately 18 ms, then the
25 Vdc steady state