Zeiss humphrey HFA II-i series, Руководство по обслуживанию на месте

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Humphrey Field Analyzer II - i Parts Removal/Replacement
Confidential and Proprietary
52235C1105 3 - 23
Field Service Guide
3.12 CRT Removal
1) Remove the operator panel (3.4).
2) Carefully discharge the CRT high voltage to ground and disconnect the high voltage
lead from the CRT.
3) Disconnect:
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the yoke connector from the CRT PCB.
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the connector at the end of the CRT neck.
4) Remove the screw (item 1, Figure 3-4) at each corner of the CRT bracket.
5) Remove the CRT assembly from the operator panel.
6) Remove the four screws (item 2, Figure 3-4) securing the CRT to the bracket. Be
careful not to lose the washers, and make note of how many washers are used on
each screw. (The washers adjust the mounted position of the CRT.)
Replacement Notes:
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Anytime the CRT or touch screen is disassembled from the foam gaskets, the CRT
and touch screen viewing surfaces should be carefully cleaned before reassembly.
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Ensure that the foam gaskets for the CRT and touch screen are sealing properly, with
no gaps between them.
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Tighten the CRT mounting screws enough to compress the foam gaskets slightly for a
good seal but DO NOT OVERTIGHTEN. If the gaskets are overcompressed, the
touch screen surface will be pressed against the operator panel bezel and the
instrument will malfunction.
Check for adequate clearance by sliding the edge of a business card between the
touch screen surface and the edge of the bezel along the entire perimeter of the bezel.
If necessary, loosen the two top CRT mounting screws slightly to obtain adequate
clearance.
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Be sure that all of the washers (spacers) are in place on the mounting screws before
securing the CRT to the bracket.
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The CRT must be mounted with its anode connector downward, and the CRT anode
lead routed over the top of the CRT neck. If the lead passes under the neck of the
CRT, it lays next to the bowl and the electrostatic field around the lead will attract dust
to the inside of the bowl.