Power Supply And Crt Display; Power Supply A N D Crt Display; Check High-Voltage Supply - Tektronix 2235A Instruction Manual

Adjustment Procedure
-
2235A Instruction
POWER SUPPLY AND CRT DISPLAY
Equlpment Requlred (See Table 4-1):
Leveled Sine-Wave Generator Digital Voltmeter
Time-Mark Generator DC Voltmeter
5 0 4 BNC Coaxial Cable
Alignment Tool
50-a BNC Termination
See ADJUSTMENT LOCATIONS 1
at the back of this manual for location of test points and adjustments.
INI'rIAL CONTROL SETrlNGS
Vertical (Both Channels)
POSITION
Midrange
MODE CH 1
VOLTS/DIV 5 mV
VOLTS/DIV Variable CAL detent
Input Coupling GND
Horizontal
POSITION
MODE
A SEC/DIV
SECIDIV ~ariabl'e
XI 0 Magnifier
Midrange
A
X-Y
CAL detent
Off (knob in)
a. Connect the digital voltmeter low lead to chassis
ground and connect the volts lead to the -8.6-V
supply (TP961).
b. CHECK-Voltmeter reading is -8.56 to -8.64V. If the
reading is within these limits, skip to part d.
c. ADJUST-The -8.6 V Adjust potentiometer (R938)
for a voltmeter reading of -8.6 V .
d. CHECK-Voltage levels of the remaining power
supplies listed in Table 5-2 are within the specified
limits.
Table 5-2
Power Supply Limits
A TRIGGER
VAR HOLDOFF NORM
Mode P-P AUTO
SLOPE Positive (button
out)
LEVEL Midrange
A & B SOURCE VERT MODE
A COUPL NORM
e. Disconnect the test equipment from the instrument.
PROCEDURE STEPS
,
CheckIAdjust Power Supply DC Levels (R938)
NOTE
2. Check High-Voltage Supply
Power
SUPP~Y
-8.6 V
+
5.2 V
+
8.6 V
+30 V
+102V
I
WARNING
)
Review the information at the beginning of the
Instrument must be turned off when removing or
Adjustment Procedure before starting this step.
replacing the crt cover and cap.
Test
Point
W961
W968
W960
W956
W954
Scans
by ARTEK MEDLA
=>
Reading
(Volts)
-8.56 to -8.64
+5.04 to +5.35
+8.43 to
+
8.77
+29.1 to +30.9
+99 to + I 0 5