Preventive Maintenance; Component Replacement - Tektronix CA PLUG-IN Instruction Manual

PREVENTIVE M AINTENANCE
Calibration
The Type CA Plug-In Unit is designed for
maximum stability and should not require f r e ­
quent recalibration.
accuracy of measurements , we suggest that you
recalibrate the instrument after every 500-
hour period of Operation (or every six months
if the unit is used intermittently). A complete
step-by-step procedure for recalibrating the
unit and checking its Operation is given in the
Calibration section of this manual. The accuracy
of measurements made with the Type CA Unit
depends not only on the accuracy of the Type
C A Unit calibration but on the
oscilloscope calibration as well. Therefore, it
is essential that the oscilloscope be maintained
in proper calibration.
Visual Inspection
Many potential and existent troubles can be
detected by a visual inspection of the unit.
fo r this reason, you should perform a com ­
plete visual check every time the instrument
is recalibrated or repaired. Apparent defects
may include loose o r broken connections, dam-
aged connectors, im properly seated
scorched or burned parts, or broken terminal
strips, as well as many other troubles. The
remedy fo r these troubles is readily apparent
except in the case of heat-damaged parts.
Damage of parts due to heat is often the direct
result of other, less apparent troubles in the
Circuit. It is essential that you determine the
cause of overheating before
damaged parts to prevent damage to the new
components.
COM PONENT REPLACEMENT
The procedures fo r replacing most parts
in the Type CA Unit are obvious.
AA
However, to insure the
associated
tubes,
replacing the
Detailed
Maintenance - Type CA
SECTION 4
MAINTENANCE
instructions fo r their removal are therefore
not required. Other components, however, can
best be removed if a definite procedure is
followed o r if certain precautions are taken.
Additional information for the replacement of
some of these parts is contained in the following
paragraphs. Because of the nature of the
instrument, replacement of certain parts w ill
require that you recalibrate portions of the
instrument to insure proper Operation. Refer
to the Calibration section
Tubes
Care should be taken both in preventive and
corrective maintenance
replaced unless they are actually causing a
definite Circuit malfunction. Many times during
routine maintenance it w ill be necessary for you
to remove tubes from their sockets.
important that these tubes be returned to the
same sockets unless they are actually defective.
Needless replacement or switching of tubes
w ill many times result
recalibration of the instrument.
require replacement, it is recommended that
they be replaced by previously checked high-
quality tubes.
Switches
Methods for removal of defective switches a re ,
fo r the most part, obvious and only a normal
amount of care is required.
are normally not replaced on the switches
used in the Type CA Unit, and if one wafer
is d efective, the entire switch should be replaced.
Switches may be ordered from Tektronix either
wired o r unwired as desired.
Soldering and Ceramic Strips
Many of the components in your Tektronix
instrument are mounted on ceram ic terminal
of this manual.
that tubes are not
It is
in unnecessary
If tubes do
Single wafers
4-1