Check Low-Frequency Linearity; Adjust Hum Balance (R470) - Tektronix 310A Instruction Manual

Performance Ch irck/Ca li bra ticM
f. Disconnect the input signal.
g. CHEC K = C RT display for s
horizontal line .

15. Check Low-Frequency Linearity

a. Reconne c t the standard amplitude c
vertical INPUT conne ct or with the 42 -inch BNC cable.
b. Set the s ta ndard amplitude ca
s q ua r e - wave output.
c. Position the d isplay to the ce
with the VERTICAL P OSI TION control.
d. Reduce the display to exactly two divisions with the
Variable VOLTS / D I V control (keep display centered about
the c e nter horizontal line).
e. Po sit ion the top of the display to the top horizontal
line of the graticule.
NOTE
Tolerances g i ven in this stop are typical values pro ­
vided as guides to corre c
are not ins tr ument s p ecifications.
f. CHECK - Vertical co m
exceed 0.1 division or expansion does not exceed 0.15
division.
g. Pos i tion the bottom of the dis
horizontal line of the gra t icule.
h. CHECK - Vertical c o mpression of display does not
exceed 0.1 division or expansion does not exceed 0.15
division.
i. Set the Variable VOLTS
BRATED.
j. Disconnect all test equipment.
16. Adjust Hum Balance
PERFORMANCE CHECK ONLY
This step is not applicable to a performance check.
Proceed to next equipme
6-11).
a. S et t he VOLTS / DIV switch to .01
5-14
i- Type 310A
t raig h t line near the center
a librator to the
l ibrator fo r a 0.5 - volt
n te r of the gra t icule
I
t ins tr ument operation, and
pression of dis p lay does not
p lay to the bottom
/ D I V control to CALI ­
n t required picture (Fig.
.
b. Connect the vertical INPUT conne
ground posts on the front panel with the 18-inch BNC-to
banana plug patch cord.
c. Connect the 10X probe to the test oscilloscope input
connector.
d. Set the test osc i lloscope for a vertical deflection
factor of 0.05 volts/division (0.5 volts/division at probe
tip), AC couple d , at a sweep rate of five milliseconds
division.
e. Connect the 10X probe tip to the hum balance test
point (see Fig. 5-10A). Connect the probe g
the Type 310A chassis near the test point,
f. ADJUS T – H um B a lance adjus
5-10B), for minimum vertical deflection on the test os
s co pe.
g. Disc o nnect all test equipment.
Fig. 5-10. (A) Location of hum balance tost point (top), (B) loca
tion of Hum Balance adjus t ment (left side ).
c tor to one of the
-
r ound s t rap to
t ment, R470 (s e e Fig.
cil lo ­
­