Troubleshooting; Troubleshooting Equipment - Tektronix 213 DMM Instruction Manual

1. Unsolder the tabs holding the terminal pin socket to the
board (located on the opposite side of the board from the
socket). Use a vacuum-type desoldering tool or solder-wick
to remove the solder. Straighten the socket tabs and re-
move the socket.
2. Install the new socket into the circuit board tab holes
and bend the tabs against the circuit board. Solder the tabs
on both sides of the circuit board. Be careful not to get sol-
der inside the socket.
CAM SWITCH REMOVAL. To remove a cam switch, per-
form the Removal and Disassembly steps for the Attenuator
Board, then remove the screws holding the cam switch to
the board. These screws are located on the opposite side of
the board from the switch.
CAM SWITCH REPLACEMENT. Before replacing a cam
switch, refer to preventive maintenance lubrication instruc-
tions for the cam switches. Replace the cam switch in the
reverse order of Removal and Disassembly. Be sure that
the flush end of the mounting bearings are facing toward
the rear of the board when installed.
CAM SWITCH CONTACT REPLACEMENT. Replacement
of the cam switch contacts requires special alignment and
spacing tools. For assistance in replacement or repair of
cam switch contacts, contact your local Tektronix Field
Office or representative.
NOTE
As special repair kits become available to the
Tektronix, Inc. Field Service centers and the
Factory Service Center, these are available also
to the user. For the latest information on kit
availability, contact your local Tektronix Field
Office or representative.
SLIDE SWITCH REMOVAL. The POWER and TRIGGER
selection slide switches are the routinely replaced solder-in
type. The INPUT COUPLING slide switch is a special Tek-
tronix designed device which may be repaired by cleaning
or parts replacement. The following instructions apply on-
ly to this switch.
To remove the special slide switch, perform the Removal
steps for the Attenuator Board and proceed as follows:
1. Unsolder the four soldered hold-down points of the
slide switch shield and remove the shield.
NOTE
At this point, the switch can be removed or dis-
assembled for inspection, cleaning, or parts re-
placement. Complete removal is explained first.
REV. A, JUNE, 1976
Maintenance-213 Service
2. Carefully remove the two nuts and spacers from the
plastic posts on the opposite side of the board. Remove
the switch by pulling it away from the board being careful
not to lose the small switch contacts under the switch.
Disassembly. The switch is further disassembled by gently
prying one of the ends away from the slider cover and re-
moving the cover and slider.
NOTE
If
the switch was intermittent, but an inspec-
tion does not reveal a fault, clean the board
contacts with a typewriter type eraser, remove
the eraser debris, reassemble the switch, and
recheck it.
Reassembly. Reassemble the slide switch in the reverse
order of Disassembly. Be careful that the switch contacts
do not become misaligned during reassembly.
SLIDE SWITCH REPLACEMENT. Replace the slide switch
in reverse order of Removal. Do not overtighten the nuts
on the plastic switch posts.
PUSHBUTTON SWITCH REPLACEMENT. Replacement
of the complete pushbutton assembly requires special align-
ment and spacing tools. For assistance in repair or replace-
ment, contact your local Tektronix Field Office or repre-
sentative.
TROUBLESHOOTING
The following information is provided to facilitate trouble-
shooting of the 213. Information contained in other sec-
tions of this manual should be used along with the follow-
ing information to aid in locating the defective component.
An understanding of the circuit operation is very helpful in
locating troubles, particularly where integrated circuits are
used.
Troubleshooting Equipment
The majority of troubleshooting to be done on the 213 can
be accomplished with two extender cards, a digital multi-
meter, a function generator, a general purpose oscilloscope,
and a line isolation transformer. If transistor and linear
integrated circuits are to be tested rather than substituted,
a curve tracer would be required. The extender cards are
the A/D Extender Card (Tektronix Part No. 067-0759-00)
and the Power Supply Extender Card (Tektronix Part No.
067-0758-00). To obtain these cards, contact your local
Tektronix Field Office or representative. Extender card
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