Figure 8-16. Liquid Crystal Test Setup - HP 5501B Operating And Service Manual

b. Place the liquid crystal in the test setup shown in Figure 8-16 below:
Do not apply DC voltages across the liquid crystal switch. Sustained dc current flow through the
c. Gently place the probes of the 50 Hz signal source on the end shoulders of the liquid
crystal as shown in Figure 8-16 and observe the window area; it should go from light to
dark while probing the device. A faint change of color or no change indicates a faulty
liquid crystal. The replacement HP part number for the liquid crystal is 1990-0768.
8-22

Figure 8-16. Liquid Crystal Test Setup

liquid crystal may damage the device.
HP5501B
Service