Tektronix 2235 - Power Supply; Preregulator; Inverter

9 . Adjust the Β DELAY TIME POSITION control clock-

1 . Preset
instrument controls and obtain α b aseline
wise to move the intensifie d zone to the leading edge of the

trace .
second point of interest (on the Α trace) ; then fine adjust
until the rising portion (on the Β trace) is centered at the
same convenient vertical graticule u sed
in preceding
step
7 .

2 . Apply an exact 5-division signal to either vertical-
channel input connector and set the VERTICAL MODE
switch to
dis
p lay
the channel u sed .
10 . R ecord t he Β DELAY TIMEPOSITION control d ial
setting .
3 . Set the appropriate V OLTS/DIV switch and Variable
control for an exact 5-division d isplay .
11 . Calculate
the time
d
ifference
b
etween repetitive
p ulses using the following formula .
4 . V ertically position the trace so that the zero r eference
Time

second

first

Α switch V

of the
waveform touches the 0% ο graticule line and t he top of
Difference =

d
ial

-

d
ial

the waveform touches the 100% graticule line .
(Duration) setting setting
setting
)
EXAMPLE
:
With t he Α SEC/DIV switch set to 0 .02 ms
p er division, the first Β DELAY TIME POSITION dial set-
ting is 1 .20 and t he second Β DELAY TIMEPOSITION
dial setting is 9 .53 (see
F
igure
4-14) .
6 . Select ALT HORIZONTAL MODE and adjust
the Β
Substituting the given values in the time difference

DELAY TIME POSITION control to intensify the transition of
formula :

interest on Α Sweep . Set the Β SEC/DIV switch to spread
the p ortion of the Α dis p lay being measure d as
much as
Time Difference = (9 .53 - 1 .20) (0 .2 ms/div) = 1 .666 ms

possible on the Β Sweep .
R ise Time
DIAL
READING

DIAL READING
AT
POINT Α

AT
POINT B
c4207-24
F ig ure 4-14 . Β D EL AY TIME P OSITIO N co n t r ol setti n gs .
Operating
Procedures-2235 ΑΝ /USM-488 Operators
5 . Set
the Α SEC/DIV switch so one transition of interest
is
d isplaye d . Ensure that the SEC/DIV Variable control is in
the
CAL d etent .
7 . Select the Β HORIZONTAL
MODE .
Adjust
the
Β DELAY TIMEPOSITION control
until the d isplay inter-
sects the 10% ο p oint at the center vertical graticule
line (see
Figure 4-15, Point Α ) .
8 . Record the Β DELAY TIME POSITION 'control dial
setting .
9 . Adjust the Β DELAY TIME
POSITION control until the
d isplay intersects the 90%
p
oint at
the center vertical grati-
cule line (see F igure 4-15, Point Β ) .
10 . R ecor d t he Β DELAY TIME
POSITION control d ial
setting .
11 . Calc u late rise time usi n g t h e same formula
liste
d
in
t he "Time Difference On Single Waveforms" measurement
procedure .
Rise-time measurementsuse the same metho d s as time
d ifference on single waveform, except that the measure
ments are ma de b etween the 10% ο and 90%
p
oints of the

EXAMPLE : With t he Α SEC/DIV switch set to
1
μs per
low-to-high transition of the selected waveform . F all time is

division, the first Β
DELAY
TIME
POSITION d ial setting
measured between t he 90% and 10%
ο p
oints of the h igh-to-

(Point Α ) is 2 .50 and the second
Β DELAYTIME POSI-
Ιοω transition of the waveform .

ΤΙΟΝ d ial setting (Point Β ) is
7
.50 .