Tektronix 535A, Инструкция по эксплуатации

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CALIBRATION
PROCEDURE
The Type 535A Oscilloscope is a stable instrument and
should not require frequent calibration. However, it will be
necessary to calibrate certain parts of the instrument when
tubes or components are changed, and periodic calibration
is desirable from the standpoint of preventive maintenance.
In the instructions that follow, the steps are arranged in
the proper sequence for full calibration. Each numbered
step contains the information necessary to make one adjust­
ment. If a complete calibration is not necessary, you may
perform individual steps, PROVIDING that the steps per­
formed do not effect other adjustments. It is most important
that you are fully aware of the interaction of adjustments.
Generally speaking, the interaction of controls will be ap­
parent in the schematic diagrams. If you are in doubt, check
the calibration of the entire section on which you are work­
ing.
If you make any adjustments on the power supplies, you
will have to check the calibration of the entire instrument.
In particular the sweep rates and vertical deflection factors
must be checked.
EQUIPMENT REQUIRED
The following equipment is necessary for a complete call
bration of the Type 535A Oscilloscope:
(1) A DC voltmeter having a sensitivity of at least 5000
<>/v and calibrated for an accuracy of at least 1% at 100,
150, 225, 350 and 500 volts, and for an accuracy of at least
3% at 1350 volts. Portable multimeters should be regularly
checked against an accurate standard and corrected read­
ings noted, where necessary, at the above listed voltages.
BE SURE YOUR METER IS ACCURATE.
(2) An accurate rms-reading ac voltmeter, having a range
of 0-150 volts. (0-250 or 0-300 for 234 v. operation).
(3) Variable auto-transformer (e.g. Powerstat or Variac)
having a rating of at least 6.25 amperes.
(4) Time-mark Generator, Tektronix Type 180, 180A or
equivalent, having markers at 1 µsec, 10 µsec, 50 µsec, 100
µsec, 1 msec, 5 msec, 10 msec, 100 msec, 1 sec, and 5 sec and
sine-wave outputs of 10 me and 50 me, all having an accur­
acy of at least 1 %.
(5) Square-Wave Generator, Tektronix Type 107 or equi­
valent, having a risetime of no more than 7 nanoseconds,
and a frequency of approximately 500 kc. The top of the
square-wave must be free of overshoot and wrinkles. A
Tektronix Type P Unit may be used in place of the Type
107. A Type P52 Coaxial Cable and a Type B52R Termin­
ating Resistor is required with the Type 107.
(6) Tektronix Type K or Type L Plug-In Unit. (If delay­
line adjustment is not required, other Tektronix Plug-In
Units may be substituted.)
(7) Low-Capacitance Recalibration Tools: Tektronix part
numbers 003-000—003-007 and 003-301. (See Recalibration
Tools in Accessories Section of Operator's Manual and. Fig.
6-1).
(8) Tektronix Type P6000 Probe.
(9) Test Oscilloscope, Tektronix Type 316 or equivalent,
providing triggered sweeps and a bandpass of at least dc
to 10 mc.
(10) Gain Set Adapter, Tektronix Type EP53A.
Fig. 6-1. Suggested Calibration Tools.
PRELIMINARY
Removing the side covers and bottom plate from the in­
strument to be calibrated and install the Type K or Type L
Unit.
Set the front-panel controls as follows:
6-1