Tektronix 7B51 Instruction Manual page 54

Type 7851
SECTIONS
PERFORMANCE CHECK
CA'-IBRA TION PROCEDURE
Change information, if any, affecting this section will be found at the rear of the manual.
Introduction
To assure instrument accuracy, check the calibration of
the Type 7B51 every 1000 hours, or every six months if
used infrequently. Before calibration, thoroughly clean and
inspect this instrument as outlined in the Maintenance
Section.
The complete Performance Check/Calibration Procedure
can be used to check instrument performance without
removing side covers or making internal adjustments, by
performing all portions except the ADJUST part of the
steps. Screwdriver adjustments which are accessible without
removing the covers are adjusted as part of the performance
check procedure. A note titled PERFORMANCE CHECK
ONL Y gives instructions which are applicable only to the
performance check procedure.
Completion of each step in the complete Performance
Check/Calibration Procedure insures that this instrument
meets the electrical specifications given in Section 1. For
best overall instrument performance, when performing a
complete calibration procedure, make each adjustment to
the exact setting even if the CHECK is within the allowable
tolerance.
A Short-Form Procedure is given prior to the complete
procedure. To facilitate instrument calibration for the
experienced calibrator, the Short-Form Procedure lists the
calibration adjustment 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. Thus, the Short-Form Procedure
can be used as an index to locate a step in the complete
procedure. Another feature of the Short-Form Procedure is
the spaces provided to record performance data or to checl~
off steps as they are completed. This procedure may be
reproduced and used as a permanent record of instrument
calibration.
®
NOTE
All waveforms shown in this procedure were taken
with a Tektronix Oscilloscope Camera System.
Limits, tolerances and waveforms in this procedure
are given as calibration guides and should not be
interpreted as instrument specifications except as
specified in Section 1.
A partial calibration is often desirable after replacing a
component or to touch up an adjustment of a portion of
the instrument between major recalibrations. For partial
calibration, set the controls as given under Preliminary
Control Setting and start with the nearest test equipment
picture preceding the desired check or checks. If any
controls need to be changed from the preliminary settings
for this portion of the calibration procedure, they are listed
under the heading Partial Procedure, following the
equipment required picture. To prevent unnecessary
recalibration of other parts of 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
of any steps listed in the INTERACTION part of the step.
TEST EQUIPMENT REQUIRED
General
The following test equipment and accessories, or its
equivalent, are required for complete calibration of the
Type 7B51. Specifications given are the minimum necessary
for accurate calibration. Therefore, some of the recom-
mended equipment may have specifications which exceed
those given. All test equipment is assumed to be correctly
calibrated and operating within the given specifications. If
equipment is substituted, it must meet or exceed the
specifications of the recommended equipment.
Special Tektronix calibration fixtures are used in this
procedure only where they facilitate calibration. These
special calibration fixtures are available from Tektronix,
Inc. Order by part number through your local Tektronix
Field Office or representative.
1. Test time-base having delaying sweep capabilities and
compatible with the Tektronix 7000-series oscilloscope.
Type 7B51 used in these checks.
2. Vertical amplifier for use with Tektronix 7000-series
oscilloscopes. Bandwidth, 100 MHz or greater; deflection
factor, 5 volts to less than 50 millivolts. Tektronix Type
7 A 16 used in these checks.
3. Oscilloscope. Tektronix Type 7504 or Type 7704.
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