Tektronix 5110, Инструкция по эксплуатации

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Maintenance-51 10
5. Clip the excess lead that protrudes through the
board (if not clipped in step 3).
6. Clean the area around the solder connection with a
flux remover solvent. Be careful not to remove information
printed on the board.
An extraction tool should be used to remove the 14- and
16-pin integrated circuits to prevent damage to the pins.
This tool is available from Tektronix, Inc. Order through
your local field office or representative. If an extraction
tool is not available when removing one of these in­
tegrated circuits, pull slowly and evenly on both ends of
the device. Try to avoid having one end of the integrated
circuit
disengage from the socket before the other, as the
pins may be damaged.
COMPONENT REMOVAL AND
REPLACEMENT
WARNING
I
To avoid electrical shock, disconnect the instrument
from the power source before replacing com­
ponents.
To replace one of the power transistors mounted on the
chassis adjacent to the Power Supply circuit board, first
unsolder the leads. Then, loosen the nuts on the plastic
bar that clamps the transistor to the chassis. Remove the
defective transistor.
When replacing the transistor, use
silicone grease on the metal tab to increase heat transfer
from the transistor to the chassis.
Semiconductor Replacement
Transistors should not be replaced unless actually
defective. If removed from their sockets during routine
maintenance, return them to their original sockets.
Unnecessary replacement of transistors may affect the
calibration of this instrument. When transistors are replac­
ed, check the performance of the part of the instrument
which may be affected.
S
CAUTION <
Power must be disconnected before removing or
replacing semiconductors to avoid component
damage.
Replacement semiconductors should be of the original
type or a direct replacement. The lead configuration of
most semiconductors used in this instrument areshown in
Fig. 4-5. Some plastic case transistors have lead con­
figurations which do not agree with those shown here. If a
replacement transistor is made by a different manufac­
turer than the original, check the manufacturer’s basing
diagram for correct basing. All transistor sockets in this
instrument are wired for the standard basing used for
metal-case transistors. Transistors which have heat
radiators, or are mounted on the chassis, use silicone
grease to increase heat transfer. Replace the silicone
grease when replacing these transistors.
WARNING
Handle silicone grease with care. Avoid getting
silicone grease in eyes. Wash hands thoroughly after
use.
Switch Replacement
Two types of switches are used in this instrument.
Contact alignment and spacing are critical to the opera­
tion of the pushbutton and cam switches. Therefore,
defective switches should either be replaced as a unit or
repaired only by personnel experienced with these types
of switches. Your local Tektronix Field Office
or represen­
tative can provide additional information. The following
special maintenance information is provided for switch
replacement.
Repair of cam switches should be undertaken only
by experienced repair personnel. Switch alignment
and spring tension of the contacts must be carefully
maintained for proper operation of the switch. For
assistance in repair of the cam switches, contact
your local Tektronix Field Office or representative.
A. CAM SWITCHES
Cam switch repair kits are available from Tektronix, Inc.
Order through your local field office or representative.
One switch kit is used to repair the cam switches in
most time-base plug-in units and some vertical plug-in
units. Another kit is used to repair the cam switches using
the high-frequency contact, which is used in several
vertical plug-in units.
The cam-type switches consist of rotating cam drums
which are turned by front-panel knobs, and sets of spring­
leaf contacts mounted on adjacent circuit boards. The
contacts are actuated by lobes on the cams. In the
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