Tektronix 5110, Инструкция по эксплуатации

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Main tenance-5110
oscilloscope system, the Volts/Div and Seconds/Div
switches are of the cam type. These switches can be
disassembled for inspection, cleaning, repair, or replace­
ment as follows:
1. Remove the screws which hold the metal cover on
the switch, and lift the cover off the switch. The switch is
now open for inspection or cleaning.
2. Remove all screws holding the board to the chassis
or other mounting surface. Some boards may be held fast
on one side by a slotted plastic bar in addition to the
screws; for these, remove the screws, then pull the circuit
board from its slot to free the board. Also, remove any
obstructions that would prevent the board from being
lifted out of the instrument.
3. Lift the circuit board out of the unit. Do not force or
bend the board.
2. To completely remove a switch from the circuit
board, first remove any knobs or shaft extensions. Loosen
the coupling at the potentiometer at the rear of the switch,
and pull the long shaft (with red knob attached) out of the
switch assembly.
4. To replace the board, reverse the order of removal.
Use care when replacing pin connectors; if forced into
place incorrectly, the pin connectors may be damaged.
3. Remove the screws (from the opposite side of the
circuit board) which hold the cam drum to the board.
4. To remove the cam drum from the front support
block, remove the retaining ring from theshaft on thefront
of the switch and slide the cam drum out of the support
block. Be careful not to lose the small detent roller.
5. To replace defective switch contacts, follow the
instructions given in the switch repair kit.
Circuit-Board Pin Replacement
Some circuit boards in this instrument are multi­
layer type boards with a conductive path(s)
laminated between the top and bottom board layers.
All soldering on these boards should be done with
extreme care to prevent breaking the connection to
the center conductor(s); only experienced
maintenance personnel should attempt repair of
these board.
6. To re-install the switch assembly, reverse the above
procedure.
B. PUSHBUTTON SWITCHES
The pushbutton switches are not repairable and should
be replaced as a unit if defective. Use a suction-type
desoldering tool to remove solder from the holes in the
circuit board when unsoldering the switches.
Circuit Board Replacement
If a circuit board is damaged beyond repair, replacethe
entire board assembly. Part numbers for completely wired
boards are given in the Replaceable Electrical Parts list.
To remove or replace a board, proceed as follows:
1. Disconnect all leads connected to the board (both
soldered lead connections and solderless pin connec­
tions).
A circuit-board pin replacement kit including the
necessary tools, instructions, and replacement pins is
available from Tektronix, Inc. Order through your local
Tektronix Field Office or representative. Replacement of
circuit-board pins on multi-layer boards is not
recommended; refer such repairs to your local Tektronix
Field Office or representative.
To replace a pin which is mounted on a circuit board,
first disconnect any pin connectors. Unsolder the damag­
ed pin and pull it out of the circuit board with a pairof pliers
(see Soldering Techniques, in this section, for
recommended soldering and unsoldering procedures). Be
careful not to damage the wiring on the board with too
much heat. The ferrule on the pin may or may not
disconnect from the hole with the damaged pin. If the
ferrule remains in the circuit board, remove the ferrule
from the replacement pin and press the new pin into the
hole in the circuit board. If the original ferrule is removed
with the damaged pin, clean out the hole using soldering-
iron heat, a solder-removing wick, and a scribe. Press the
replacement pin with attached ferrule into the circuit­
board hole. Position the replacement pin in the same
manner as the removed pin. Solder the pin to the circuit
board on each side of the board. If the removed pin was
bent at an angle to mate with a connector, carefully bend
the new pin to the same angle. Replace the pin connector.
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