Tektronix 310A, Instruction Manual, Page: 60 / 132

Performance Check/Calibration-Type 310A
F<g. 5-4. Lo cation of DC Bal a d ju itm a n t (lo ft tid a l,
PERFORMANCE CHECK O NLY
The remainder of this step is not applicable to a
performance check. If there is no trace on the CRT at
this point, adjust the PRESET ADJUST as follows
(this procedure may not provide correct instrument
performance under all operating conditions): (1)
Rotate the PRESET ADJUST fully counterclockwise
and then slowly rotate it clockwise until a trace first
appears on the CRT; note the physical rotation of the
adjustment. (2) Continue rotating the PRESET
ADJUST until the trace brightens; again note the
rotation. (3) Set the PRESET ADJUST midway
between the position noted in parts (1) and (2). (4)
Proceed to next step.
b. Connect the 10X probe to the test oscilloscope input
connector.
c. Set the test oscilloscope for a vertical deflection
factor of 0.5 volts/division (5 volts/division at probe tip),
DC coupled, at a sweep rate of one millisecond/division.
d. Connect the 10X probe tip to the preset test point
(junction of C101-R100. see Fig. 5-5A). Connect the probe
ground strap to the Type 31OA chassis near the test point.
e. Rotate the PRESET ADJUST, R126 (see Fig. 5-5B),
fully counterclockwise. Then, slowly rotate it clockwise
until the trace first appears on the Type 310A CRT. Adjust
the test oscilloscope vertical position control to move the
trace to a graticule line near the center horizontal line.
f. Continue rotating the PRESET ADJUST clockwise
until the trace on the Type 310A CRT brightens. Note the
location of the trace on the oscilloscope CRT.
g. A D JUST-Rotate the PRESET ADJUST counter
clockwise until the trace on the test oscilloscope is located
half way between the trace location in parts e and f.
h. Disconnect all test equipment.
Fig. 5 6 . (A ) Lo catio n o f p raia t t a il p o in t (inside swing-out chassis),
(B) location of P R E S E T A D J U S T (fro n t panal).
8. Check/Adjust Astigmatism
a. Connect the CAL OUT binding post to the vertical
INPUT connector with the 18-inch BNC-tobsnana plug
patch cord.
b. Set the CALIBRATOR switch to .5.
c. Center the display on the CRT area with the V E R T I­
CAL POSITION and HORIZO NTAL POSITION controls.
d. C H E C K -C R T display should be well defined with
optimum setting of the FOCUS CONTROL.
PERFORMANCE CHECK ONLY
Rear-panel operational adjustment; can be adjusted as
part of a performance check.
e A D JU ST-FO C US control and ASTIG adjustment.
R750 (see Fig. 5-6), for best definition of the CRT display.
9. Check/Adjust CRT Alignment
a. Connect the vertical INPUT connector to one of the
ground posts on the front panel with the 18-inch BNC-to-
banana plug patch cord.
b. Position the trace to the center horizontal line with
the VER TICA L POSITION control.
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5-10