Tektronix 310A, Instruction Manual, Page: 51 / 132

Type 310A
SECTION 5
PERFORMANCE
CHECK/CALIBRA TION
Change inform ation, if any, affecting this section w ill be found at the rear o f this manual.
Introduction
To assure instrument accuracy, check the calibration of
the Type 310A every 500 hours of operation, or every six
months if used infrequently. Before complete calibration,
thoroughly clean and inspect the oscilloscope as outlined in
the Maintenance section.
As an aid to calibration, a Short-Form Procedure is given
prior to the complete procedure. To facilitate instrument
calibration fo r the experienced calibrator, the Short-Form
Procedure lists the calibration adjustments necessary for
each step and the applicable tolerances. This procedure also
includes the step, number and title as listed in the Complete
Performance Check/Calibration Procedure and the page
number on which each step begins. Therefore, the Short-
Form Procedure can be used as an index to locate a step in
the complete procedure. Another feature o f the Short-
Form Procedure is the spaces provided to record perform ­
ance data or to check o ff steps as they are completed. This
procedure can be reproduced and used as a permanent
record o f instrument calibration.
The Complete Performance Check/Calibration Procedure
can be used to check instrument performance w ithout
removing the covers or making internal adjustments by
performing all portions except the ADJUST- part o f a step.
Screwdriver adjustments which are accessible w ith o u t
removing the covers are adjusted as part o f the performance
check procedure. A note title d PERFORMANCE CHECK
O NLY gives instructions which are applicable only to the
performance check procedure and lists the next applicable
performance check step.
Completion o f each step in the Complete Performance
Check/Calibration Procedure insures that this instrument
meets the electrical specifications given in Section 1. Where
possible, instrument performance is checked before an
adjustment is made. For best overall instrument perform ­
ance when performing a complete calibration procedure,
make each adjustment to the exact setting even if the
CHECK- is w ithin the allowable tolerance.
NOTE
Lim its and tolerances in this procedure are given as
calibration guides and should not be interpreted as
instrum ent specifications except as specified in
Section 1.
A partial calibration is often desirable after replacing
components or to touch up the adjustment of a portion of
the instrument between major recalibrations. To check or
adjust only part of the instrument, start w ith the nearest
equipment required picture preceding the desired portion.
To prevent unnecessary recalibration o f other parts o f the
instrument, readjust only if the tolerance given in the
CHECK- part of the step is not met. If readjustment is
necessary, also check the calibration o f any steps listed in
the INTERACTION- part o f the step.
TEST EQUIPM ENT R EQ U IR ED
General
The following test equipment and accessories, or its
equivalent, is required fo r complete calibration o f the Type
310A. Specifications given are the minimum necessary for
accurate calibration. Therefore, some o f the recommended
equipment may have specifications which exceed those
given. A ll test equipment is assumed to be correctly cali­
brated and operating w ithin the given specifications. If
equipment is substituted, it must meet or exceed the speci­
fications o f the recommended equipment.
Special Tektronix calibration fixtures are used in this
procedure only where they facilitate quick and more
accurate calibration. These special calibration fixtures are
available from Tektronix, Inc. Order by part number
through your local Tektronix Field Office or representative.
Test Equipment
1. Variable autotransformer.1 Must be capable o f
supplying about 200 vo lt amperes over a range o f 99 to 132
volts (198 to 264 volts fo r 234-volt nominal line). (If auto­
transformer does not have an AC voltmeter to indicate out
put voltage, m onitor the output w ith an AC RMS-reading
v o ltm e te r.) For example. General Radio W10MT3W
Metered Variac Autotransformer.
2. DC vo ltm e te r1 Minimum sensitivity, 20,000 ohms/
volt; range, 0 to 1750 volts; accuracy, checked to w ithin
1% at 100, 150, 300 and 1675 volts. For example, T rip lett
Model 630-NA.
3. Test Oscilloscope.1 Bandwidth, DC to 500 kilohertz;
minimum deflection factor, 10 m illivolts/division; accuracy,
w ithin
3% .
Tektronix Type 561A Oscilloscope w ith Type
3A72 A m p lifie r unit and Type 2B67 Time Base unit recom­
mended^
1 N o t required fo r perform ance check only.
5-1