Replacing Parts; How To Replace Semiconductors; How To Remove The Housekeeper Integrated Circuit - Tektronix 11A52 Service Manual

Maintenance
7. Do not slide the components over any surface.
8. A void handling components in areas that have a floor or work-surface covering capable of generating a
static charge.
9. Use a soldering iron that is connected to earth ground.
10. Use only special antistatic suction type desoldering tools.
Replacing Parts
CAUTION
To avoid component damage, disconnect the power plug and unplug the 11A52 from the oscilloscope
before removing or replacing components.
The exploded-view drawing associated with the Replaceable Mechanical Parts list (located at the rear of this
manual) may be helpful in the disassembly procedures that follow.
How to Replace Semiconductors
Semiconductors should be replaced only when defective. If removed from their sockets during routine
maintenance, return them to their original sockets. Unnecessary replacement of semiconductors may affect the
adjustment of the amplifier. When semiconductors are replaced, check the operation of circuits which may be
affected.
Replacement semiconductors should be of the original type or a direct replacement. Lead configurations of the
semiconductors used in this oscilloscope are shown in Figure 3-8, Semiconductor Lead Configurations, in this
section.
CAUTION
Do not remove stickers affixed to the top of EPROMs. Removing this sticker
will
allow light into
the chip, and may cause partial erasure of its data.
How to Remove the Housekeeper Integrated Circuit
When the Housekeeper IC is installed, the beveled comer of the IC is aligned with a spring at one comer of the
socket. The other IC comers are notched and fit the edges of the socket.
1. Unfasten the retaining clip by moving it across the tabs. It may help to push down slightly on the cover.
2. Remove the cover slowly to prevent the IC from falling out. Notice the position of the IC before removing.
3. Remove the IC with tweezers.
CAUTION
Avoid touching the IC or the socket contacts with your fingers. Finger oils can lessen reliability.
11A52 Extended Service Manual
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