Tektronix 2235 Operator's Manual

Operating
Procedures-2235 ΑΝ /USM-488
Operators
Α TRIGGER LEVEL control
to its fully clockwise p osition ;

7 . To display α
selecte d h orizontal line, first trigger the
for

negative-going

TV

signal

sync

p ulses,

set

the

sweep on α vertical (field)
sync pulse, then use the
"Magni-
Α

TRIGGER

SLOPE

switch

to

IN

and

ad just

the

fied Sweep Runs After
Delay" p roce d ure in t his
part (steps 5
Α TRIGGER LEVEL control
to its fully counterclockwise

and
6) to magnify the selected h
orizontal line for α
closer
position .

examination . This procedure
is useful for examining V ertical
Interval Test Signals (VITS) .
T V Field Signal
ΝΟΤΕ
To
exami n e α T VL ine
signal in mo r e d etail,
either the
Χ 10 Magnifier or t he
Delayed-Swee p
Magnification
feat u re may b e used
.
The television feature of this
instrument can also b e used
to d isplay TV Field signals .
1 . Preset instrument
controls and o btain α baseline
trace .
2 . Select TV FIELD Α T
RIGGERmode (push both Ρ - Ρ
AUTO and NORM
buttons in) an d set the Α SEC/DIV switch
to 2 ms .
3 .
To
d isplay α signal
field, connect the TV signal to ei-
ther vertical-channel in p ut connector
and set the VERTICAL
MODE switch to display
the channel used .
4 . Set the a pp ro p riate V
OLTS/DIV switch to display
1-division or more of composite
sync signal .
5 . For positive-going TV
signal sync p ulses, set the Α
TRIGGER SLOPE switch to OUT
and adjust the Α TRIG-
GER LEVEL control to its fully
clockwise p osition ; for
n egative-going TV signal
sync p ulses, set the Α TRIGGER
SLOPE switch to IN an d adjust the Α
TRIGGER LEVEL
control to its fully counterclockwise
p osition . It may b e nec-
essary to adjust the V AR HOLDOFF
control to obtain α sta-
ble triggering of the d esired TV field
.
6 . To change the TV field that
is displayed, momentarily
interrupt the trigger signal
by setting the Input Coupling

Using d elaye d -swee p
magnification may pro d uce α dis-
switch to GND and t hen back
to DC or AC until the d esired

with some slight h
orizontal movement
field is displayed .

play

(pulse j ittery .
Pulse j itter includes n ot
only
the
inherent uncertainty of trig
NOTE

gering the delayed sweep at
exactly the same trigger p oint
each time, but also j itter that
may be p resent in the input
To
exami n
e αT VF ield sig n al In more
d etail, either t he

signal . If pulse j itter nee d s to b e measured,
use the "Pulse
Χ 10
Magnifier or Delayed-Sweep Magnification
may

J itter Time Measurement" proced ure which
follows the d is-
be use d .

cussion
of "Magnified Sweep Runs After
Delay ."
8 . To d isplay Field 1 and F ield 2
on separate channels,
connect the
TV signal to b oth input
connectors, then
select
BOTH and A LT
VERTICAL MODES
. Set the Α SEC/DIV
switch to
0 .5 ms or faster sweep speed
(dis p lays less than
one full
field) . This will synchronize the
Channel 1 d isplay to
one field and
the Channel 2 d isplay
to the other field .
DEL AY E D-S WEEP M
AG N I F ICATIO N
The delayed-sweep
feature of this instrument can
b e
use d to provide h igher
apparent magnification than
is pro-
vi
d ed by the Χ 10 Magnifier
switch . Apparent magnification
occurs as α result of
d isplaying α selected portion of the Α
t race at α faster sweep
speed ( Β Sweep s pee d ) . The
Α
SEC/DIV switch setting
determines h ow often t he Β
trace
will be d isplayed .
Since the Β Sweep can occur
only once
for each Α
Sweep, the Α Sweep time d uration sets the
a m ount of time elapse b etween
succeeding Β Sweeps .
The intensifie
d zone is an in d ication of both
t he location
and length of the Β
Sweep i nterval within
the Α Sweep inter-
val . Positioning
of the intensified zone
(i .e ., setting the
amount of time
between start of the Α Sweep
and start of
the Β Sweep) is
accomplishe d with t he Β DELAY
TIME PO-
SITION control . W ith
either ALT or Β H
ORIZONTAL MODE
selected an d Β T
RIGGER LEVEL control set fully
clockwise
( Β RUNS AFTER
DLY), the Β DELAY
TIME POSITION con-
trol provides
continuously variable positioning
of the start of
the Β Sweep . The range
of this control is
sufficient to place
the Β Sweep interval
at any location within t
he
Α
Sweep
interval except the first
0 .5 division . When ALT
HORIZON-
TAL MODE is selecte
d , the Β SEC/DIV switch setting
d eter-
mines the Β Swee p
speed an d concurrently
sets the length
of the intensifie
d zone on the Α trace .

Tektronix 2235 Specifications

General

Brand	Tektronix
Model	2235
Category	Test Equipment
Language	English