Low-Frequency Linearity; Ch 1 And Ch 2 Vertical Deflection Accuracy; Ch 3 And Ch 4 Vertical Deflection Accuracy; S Ignal-To-G Raticule Accuracy - Tektronix 2246 1Y Service Manual

Performance Check Procedure —2246 1Y and 2246 Mod A Service
f. Set:
CH 1 VAR VOLTS/DIV
Vertical MODE
CH 2 VOLTS/DIV
g. Position CH 2 trace to the center horizontal graticule
line.
h. Move the test signal to the CH 2 input.
i. Set CH 2 VAR VOLTS/DIV
j. Repeat the CHECK procedure for CH 2.
k. Set CH 2 VAR VOLTS/DIV to detent (calibrated) posi­
tion.

8. Low-Frequency Linearity

a. Set:
Vertical MODE
CH 1 VOLTS/DIV
SCOPE BW
b. Set calibration generator AMPLITUDE to 20 mV.
c. Move the test signal to the CH 1 input.
d. Position the top of the signal to top graticule line.
e. Check the signal amplitude is between 1.9 and 2.1
divisions.
f. Set bottom of the signal to bottom graticule line.
g. Check the signal amplitude is between 1.9 and 2.1
divisions.
h. Repeat the procedure for CH 2.

9. CH 1 and CH 2 Vertical Deflection Accuracy

a. Set CH 2 VOLTS/DIV to 2 mV.
b. Set calibration generator AMPLITUDE to 10 mV.
c. Position the trace two graticule lines below the cen­
ter graticule line.
d. CHECK—all positions of the VOLTS/DIV settings for
correct signal-to-graticule accuracy, using the set­
tings in Table 4-2 for the checks.
e. Set calibration generator to Std Ampl output, 10 mV.
4 -8
Detent
(calibrated)
CH 2 (CH 1 off)
10 mV
fully CCW.
CH 1 (CH 2 off)
10 mV
On
f. Move the test signal to the CH 1 input.
g. Set:
Vertical MODE
CH 1 VOLTS/DIV
h. Position the trace two graticule lines below the cen
ter graticule line.
i. Repeat CHECK procedure for CH 1.
Table 4 -2

S ignal-to-G raticule Accuracy

VOLTS/DIV Calibration
Setting Generator
AMPLITUDE Setting
2 mV 10 mV
5 mV 20 mV
10 mV 50 mV
20 mV 100 mV
50 mV 200 mV
0.1 V 500 mV
0.2 V 1 V
0.5 V 2 V
1 V 5 V
2 V 10 V
5 V 20 V

10. CH 3 and CH 4 Vertical Deflection Accuracy

a. Set:
Vertical MODE
CH 3 & CH 4 VOLTS/DIV
b. Position the trace two graticule lines below the cen­
ter horizontal graticule line.
c. Move CH 1 test setup to the CH 3 input.
d. Set calibration generator AMPLITUDE to 0.5 V.
e. CHECK-the signal amplitude is between 4.90 and
5.10 divisions.
CH 1 (CH 2 off)
2 mV
Deflection
Accuracy
(in divisions)
4.90 to 5.10
3.92 to 4.08
4.90 to 5.10
4.90 to 5.10
3.92 to 4.08
4.90 to 5.10
4.90 to 5.10
3.92 to 4.08
4.90 to 5.10
4.90 to 5.10
3.92 to 4.08
CH 3 (CH 1 off)
0.1 V
REV JUN 1991