Calibration Procedure - Tektronix Type B Plug-In Instruction Manual

General
The Type B is a stable instrument and should not require
frequent calibration.
after tube replacements or extensive maintenance work to
check the adjustment of certain important controls to insure
precise and accurate operation of the plug-in unit.
Equipment Required
Before calibrating your Type B, be sure that the Type 530-
or 540-Series Oscilloscope you are using has been checked
for power supply outputs, power supply ripple and regula­
tion, vertical am plifier gain, vertical amplifier band pass
and calibrator accuracy.
Other equipment required includes:
Type 190 or 190A Constant-Amplitude Signal Generator
or equivalent, providing constant amplitude sine waves from
about 50 kc to 30 me with output amplitude constant within
± %.
2
Type 105 Square-Wave Generator or equivalent with fre­
quency range of about 25 cycles to 1 me, rise time at least
.02 microseconds and frequency indication accuracy of no
poorer than ± 3 % .
Type 107 Square-Wave Generator or equivalent with fre­
quency range of 400 kc to 1 me, peak-to-peak output volt­
age of at least 0.1 to .5 volts, and risetime o f 3 nanoseconds
or less.
Input capacitance standardizer, (CS 47), 52 Cl Terminating
Resistor, 5:1 L pad, 52 Cl cable and 52 f i terminating resistor.
Adjustment Procedure.
1. The first step in calibration of your Type B should be
to determine the "Vertical
your test scope. If a test load unit is available, insert it in
the oscilloscope. Depress the PRESS TO SHORT button and
observe the vertical level of the trace. This can also be ac­
complished by placing a jumper between pins 1 and 3 of
the interconnecting plug on your Type B Unit, thus shorting
the plug-in output, and again observing the vertical level
of the CRT trace. This level is referred to later in the cali­
bration procedure.
2. Before starting calibration o f your Type B Unit, be sure
that the left side and bottom panels are removed from your
oscilloscope. Unless otherwise specified, oscilloscope con­
trols w ill be set as follows:
http://manoman.sqhill.com
However, it is sometimes necessary,
System Electrical Center" of
CALIBRATION
PROCEDURE
HORIZONTAL DISPLAY
TRIGGERING MODE
TRIGGER SLOPE
STABILITY
TIME/CM
3. Adjust DC BAL.
Position the trace on the oscilloscope to about the cen­
ter horizontal graticule line.
trace does not shift vertically while the VARIABLE VOLTS/
CM control is shifted throughout its range.
4. Adjust Vert. Pos. Range.
Set the VERTICAL POSITION knob at mid-range. Adjust
the VERT. POS. RANGE or POSITIONING ADJ. control so
that the trace is at " Vertical-System Electrical Center."
5. Set G A IN ADJ.
From the CALIBRATOR of the oscilloscope, apply .2 volts
to INPUT A and set G AIN ADJ. 1 for 4 cm of vertical de­
flection. Set VOLTS/CM switch to .005 and apply 20 m illi­
volts from the CALIBRATOR to INPUT A. Set G AIN ADJ.
2 for 4 cm of vertical deflection.
6. Adjust M ain Amplifier Input Capacitor.
Set plug-in controls to INPUT A, DC, VOLTS/CM to .05
and VARIABLE to CALIBRATED. Connect the Input Capaci­
tance Standardizer to INPUT A. From the Type 105, apply
a 1 kc signal. Adjust the Type 105 OUTPUT AMPLITUDE
for 3.5 cm o f vertical deflection on the scope.
Units S /N 101 through 3300, adjust C3002 for the best
square wave. For S/N's 3301 and up, adjust C3262.
7. Adjust VOLTS/CM Switch Compensations.
Leave the Type 105 and Type B set as in the previous
step, with the exception of the Type B VOLTS/CM Switch.
In Type B Units S /N 101 through 3300, adjust the 1 kc
square wave from the Type 105 for optimum square corner
and optimum fla t top as follows:
VOLTS/CM FLAT TOP ADJUST
0.1 C3162
.2 C3192
.5 C3092
5.0 C3132
OIM S
M AIN OR " A " SWEEP,
NORMAL
AUTOMATIC
- I N T
PRESET
1 MILLISEC
Adjust DC BAL so that the
In Type B
SQUARE CORNER
ADJUST
C3172
C3202
C3102
C3142
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