Tektronix 2445, Instruction Manual

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Performance Check— 2445 Service
23. Press and release the AV pushbutton to reobtain the
AV readout display.
24. Repeat subparts 5 through 23 of part e for each
VOLTS/DIV setting listed in Table 4-2.
25. Set the TRIGGER COUPLING switch to NOISE
REJ.
26. Set the CH 1 and CH 2 Input Coupling switches to
50 mV.
27. CHECK— Trigger Level Readout is within the limits
given in Table 4-2 for NOISE REJ Coupling.
f. Return the TRIGGER COUPLING switch to DC.
g. Set the CH 1 VOLTS/DIV switch and the Calibration
Generator output level to produce a vertical signal display 5
divisions in amplitude.
Table 4-2
Accuracy Limits
CH 1, CH 2, CH 2 INVERT, and Delta Volts Readouts
VOLTS/
DIV
Switch
Setting
CH 1
and
CH 2
Stand­
ard
Ampli­
tude
Input
Level
Vertical
Deflection
Accuracy
( ± 2 % in
divisions)
Delta Volts
Readout
Accuracy
(limits)
2% +.03 div
Limits of Trigger LEVEL
Readout
DC Coupling NOISE REJ Coupling
+ Peak
— Peak +Peak —Peak
2 mV 10 mV 4.90 to 5.10 9.70 mV to 10.30 mV 8.5 mV to 11.5 mV + 1.2 mV to —1.2 mV
5 mV 20 mV 3.92 to 4.08 19.4 mV to 20.6 mV 17.3 mV to 22.7 mV +2.1 mV to —2.1 mV
10 mV 50 mV 4.90 to 5.10 48.4 mV to 51.6 mV 44.5 mV to 55.5 mV
+ 4 mV to —4 mV
20 mV 0.1 V 4.90 to 5.10 97.5 mV to 102.56 mV 89 mV to 111 mV
+7.5 mV to - 7 .5 mV
50 mV 0.2 V 3.92 to 4.08 194 mV to 206 mV 177 mV to 223 mV
+ 17 mV to —17 mV 147 mV to
253 mV
+47 mV to
- 4 7 mV
0.1 V 0.5 V 4.90 to 5.10
486 mV to 514 mV 0.449 V to 0.551 V +0.036 V to -0 .0 3 6 V
0.2 V 1.0 V
4.90 to 5.10
0.975 V to 1.025 V 0.90 V to 1.10 V +0.07 V to -0 .0 7 V
0.5 V
2.0 V 3.92 to 4.08
1.94 V to 2.06 V 1.78 V to 2.22 V +0.14 V to -0 .1 4 V
1.0 V 5.0 V 4.90 to 5.10 4.86 V to 5.14 V 4.50 V to 5.50 V +0.35 V to -0 .3 5 V
2.0 V 10.0 V
4.90 to 5.10
9.75 V to 10.25 V
9.0 V to 11.0 V
+0.7 V to - 0 .7 V
5.0 V 20.0 V 3.92 to 4.08
19.4 V to 20.6 V 17.8 V to 22.2 V + 1.4 V to - 1 .4 V
h. CHECK— Display amplitude reduces to 2 divisions or
less when the VOLTS/DIV VAR control (of the channel un­
der test) is rotated fully CCW. Return the VOLTS/DIV VAR
control to its maximum CW (detent) position.
i. Set the Calibration Generator output level and VERTI­
CAL POSITION controls for a 2-division display vertically
centered on the graticule. Use the CH 1 VAR control if nec­
essary to obtain the correct display amplitude.
j. Set the VERTICAL POSITION control to align the top
edge of the display with the top graticule line.
k. CHECK— Signal display amplitude is 1.9 to 2.1
divisions.
I. Set the VERTICAL POSITION control to align the bot­
tom edge of the signal display with the bottom graticule line.
4-7