Tektronix 2215A User Manual

Adjustment Procedure—2215A Service
2. Check High-Voltage Supply
WARMING
Instrum ent m ust be turned o ff when rem oving o r re
placing the c rt cover and cap.
a. Remove the crt cover and cap and connect a dc volt
meter capable of measuring at least —2500 V between pin
2 of the crt socket and chassis ground. Pin 2 of the crt is
negative with respect to the chassis.
b. CHECK—Voltmeter reading is between —1900 V and
-2100 V.
c. Disconnect the voltmeter leads and replace the crt cap
and cover.
3. Adjust CRT Grid Bias (R851)
a. Connect a 50-Q termination to the EXT Z AXIS INPUT
connector located on the rear panel.
b. Adjust the front-panel FOCUS control to produce a
well-defined dot.
c. Rotate the A INTENSITY control fully counterclock
wise.
d. ADJUST—Grid Bias (R851) for a visible dot. Then
back off the Grid Bias potentiometer until the dot just
disappears.
e. Disconnect the 50-Q termination from the EXT Z AXIS
INPUT connector.
4. Adjust Astigmatism (R874)
a. Set:
A INTENSITY Visible display
Channel 1 Input Coupling DC
A SEC/DIV 5 ms
b. Connect the leveled sine-wave generator output via a
50-Q cable and a 50-Q termination to the CH 1 OR X input
connector.
c. Set the generator to produce a 50-kHz, 4-division
display.
d. ADJUST—Astig (R874) and the front-panel FOCUS
control for the best defined waveform.
e. Disconnect the test equipment from the instrument.
5. Adjust Trace Alignment
a. Set the Channel 1 Input Coupling switch to GND and
position the trace to the center horizontal graticule line.
b. ADJUST—The front-panel TRACE ROTATION con
trol for optimum alignment of the trace with the center hori
zontal graticule line.
6. Adjust Geometry (R870)
a. Set:
CH 1 VOLTS/DIV 50 mV
CH 1 Input Coupling DC
A SEC/DIV 0.1 ms
b. Connect 20 -m s time markers from the time-mark gen
erator via a 50-Q cable and a 50-Q termination to the CH 1
OR X input connector.
c. Adjust the Channel 1 POSITION control fully counter
clockwise to position the baseline part of the display below
the bottom horizontal graticule line.
d. ADJUST—Geom (R870) for minimum curvature of the
time markers at the left and right edges of the graticule.
e. Set the Channel 1 Input Coupling switch to GND.
f. ADJUST—Geom (R870) for minimum curvature of the
baseline trace when positioned at the top and bottom hori
zontal graticule lines using the Channel 1 POSITION
control.
g. Set the Channel 1 Input Coupling switch to DC.
h. Repeat parts d through g for optimum compromise
between the vertical and horizontal displays.
i. Disconnect the test equipment from the instrument.
5 -5

Tektronix 2215A Specifications

General

Brand	Tektronix
Model	2215A
Category	Test Equipment
Language	English