Power Supply, Display, And Z-Axis; Initial Control Settings; Procedure; Power Supply Dc Levels (R2252) - Tektronix 2246 1Y Service Manual

Adjustment Procedure—2246 1Y and 2246 Mod A Service

POWER SUPPLY, DISPLAY, AND Z-AXIS

Equipment Required (See Table 4-1):
Digital Multimeter (DMM)
Leveled Sine— Wave Generator
Test Oscilloscope w/lO X Probe
at the back of this manual for locations of test points and adjustments.

INITIAL CONTROL SETTINGS

1. Set:
Vertical MODE
CH 1 COUPLING
VOLTS/DIV
Vertical POSITION
Controls
Horizontal MODE
A/B SELECT
SEC/DIV
Trigger LEVEL
HOLDOFF
SLOPE
Trigger MODE
Trigger SOURCE
Trigger COUPLING
MEASUREMENTS
MENU Displays
A INTEN
READOUT
FOCUS
SCALE ILLUM

PROCEDURE

1. Power Supply DC Levels (R2252)

a. Connect a Digital Multimeter (DMM) negative
lead to chassis ground. Connect positive lead to
5-4
See the ADJUSTMENT LOCATIONS section
CH 1
DC
0.1 V
12 o 'clock
A
A
0.1 ms
12 o 'clock
min (CCW)
-J~
AUTO LEVEL
CH 1
DC
OFF
OFF
10 o 'clock
12 o 'clock
for well defined display
fully CCW
50 n Coaxial Cable
50 f l Termination
first test point listed in Table 5-2 (all test points
on J1204, Main board).
b. CHECK—Voltage reading is within the range
given in Table 5-2.
c. Move DMM positive lead to each of the other
supply voltages in Table 5-2 and check that
voltage ranges are within limits.
NOTE
If all supply voltages are within the limits
given in Table 5-2, it is not necessary to
adjust the power supply. If voltages are not
within limits, you will have to adjust the
+7.5 V supply, recheck the other voltages,
and continue with a complete readjustment of
the instrument.
d. Connect a Digital Multimeter (DMM) negative
lead to chassis ground and positive lead to
+7.5 V test point (J2104-8).
e. ADJUST—+7.5 V ADJ (R2252) for +7.5 V and
check that all supply voltages in Table 5-2 are
within limits. The
accessible through the right side frame.
f. Disconnect Digital Multimeter.
+7.5 V Adjustment is