Tektronix T921 User Manual

The T921, T922, and T922R will operate
from either a
120
V
or
240
Vac, 50 to
60 Hz nominal power input source .
To
avoid equipmentdamage, the power input range
selector switch (120 V or 240 V) and HI/LO switch on the
bottom of the instrument (T921/T922 only) mustbe set to
positions which include the value of the applied power
input voltage . The POWER indicator lamp will
blink when
the applied power
input voltage varies more than about
10% from the value for which the switches are set .
To avoid electric shock and equipmentdamage, do
not attempt to change the power input range
selector
switch, HI1LO switch, or internal fuse . This
must
be done by qualified service personnel only .
The T921, T922, and T922R operate from a single-
phasepower source with one of the current-carrying
conductors (the neutral conductor) at ground (earth)
potential .
Operation
from power
sources
where both
current-carrying conductors are live with respect to
ground (such as phase-to-phase on a 3-wire system) is not
recommended, since only the line conductorhas over-
current (fuse) protection within the instrument .
The T921, T922, and T922R have a 3-wire cord with a 3-
terminal polarized plug for connection to the power
source and safety-earth . The ground terminal of the plug
is directly connected to the metal parts of the
instrument .
For
electric-shock protection, insert this plug in a
mating
outlet with a safety-earth contact .
FUNCTIONS
OF CONTROLS,
CONNECTORS, AND INDICATORS
T921 AND T922
(See text preceding FIRST TIME OPERATION for
features found only in T922R or those which differ
from the T921/T922 .)
Before you turn the instrument on, read this portion of the
manual
to
familiarize
yourself
with the
controls,
connec-
tors, and indicators .
REV . A, JUNE 1976
OPERATING INSTRUCTIONS
OPERATING VOLTAGE
WARNING
SAFETY INFORMATION
NOTE
Front Panel
(Fig . 2-1)
Section 2-T921 /T922/T922R
A . DISPLAY
INTENSITY-Adjusts the brightness of the crt dis-
play . Set for the lowest visible display to prolong
crt
life .
FOCUS-Adjusts for optimum spot
size and defini-
tion .
( 3 )BEAM FINDER--Locates
off-screen displays . Com-
presses the crt display to
within the graticule area
independently of
the position control or applied
signals .
To locate an off-screen display :
a . Set the vertical
POSITION and INTENSITY
controls to
midrange and rotate the horizontal
POSITION control clockwise .
b . If a display or dot
still
is
not visible, press
BEAM FINDER and
hold in . A compressed dis-
play or
dot should appear . If not, increase
the
INTENSITY until a display appears .
If a dotor vertical line appears,
the sweep is not
triggered . Set the
trigger MODE switch to AUTO
to obtain a
display . Use the vertical and horizontal
POSITION controls to move the display near the
center of the graticule . Release the
BEAM
FINDER button and adjust
the trigger level con-
trol for a stable
display .
If a compressed display appears, adjust
the
VOLTS/DIV switch and the horizontal
and ver-
tical POSITION controls for a
stable display .
0
PROBE ADJ-Provides a square-wave output of
approximately 0 .5 V (negative-going with
respect to
ground) at approximately
1 kHz, for compensating
voltage probes .
ON-OFF-Push-push switch turns the instrument
power on (button in) and off (button
out) . (In some
versions this switch is
labeled POWER .)

Tektronix T921 Specifications

General

Brand	Tektronix
Model	T921
Category	Test Equipment
Language	English