Tektronix 2445 User Manual

Basic Applications—2445 Operators
DELTA
CURSOR
SIGNAL
3 8 3 2 -1 9
Figure 6-7. Phase difference between two time-related signals.
3. Press in the X10 MAG push button to obtain the
magnified display and use the Horizontal POSITION and
A REF OR DLY POS controls to align the reference
zero-crossing with the Reference cursor.
4. Align the Delta cursor with the second comparison
zero-crossing (see Figure 6-8).
5. Read the (magnified) phase difference in degrees
from the crt readout. Divide this reading by 10 to obtain
the correct phase difference between the two signals.
DIVIDE BY 10
DELAYED-SWEEP OPERATION
The 2445 offers three delayed-sweep operating modes:
the A Intensified Sweep, the A Intensified Sweep alternated
with the B Delayed Sweep, and the B Delayed Sweep.
Appropriate use for these modes varies with the particular
application, but in general they are used most frequently
for making timing measurements and for examining specific
points of interest within a waveform or pulse train.
A Intensified Horizontal Display Mode
The A Intensified Horizontal Display mode is entered
by pulling out the B SEC/DIV knob (PULL-INTEN) while
both the A SEC/DIV and the B SEC/DIV switches are at
the same setting. In this mode only the A Sweep is
displayed, with a short intensified zone imposed on it. The
position and length of the intensified zone indicates the
delay-time position and the B Sweep interval respectively.
A DLY readout appearing in the crt display gives the time
delay between the start of the A Sweep and the start of the
B Sweep. Positioning the .intensified zone to a point of
interest on the A Sweep trace is accomplished using the A
REF OR DLY POS control. Rotating the control continu
ously changes the DLY readout seen on the crt. With the B
TRIGGER MODE set to RUN AFT DLY, the position of
the intensified zone on the A Sweep trace also is continu
ously variable and follows the delay change smoothly.
NOTE
If the B TRIGGER MODE is set to TRIG AFT DL Y
for triggered B Sweep operation, the A REF OR DL Y
POS control does not continuously position the
intensified zone on the A Sweep trace. In this case,
the intensified zone jumps to each succeeding B
Trigger point within the A Sweep interval as delay
time is changed.
Once the intensified zone is positioned at the point of
interest, switching to the Alternate Horizontal Display
mode (TURN-ALT) offers a convenient sweep display for
either examining that point in greater detail or making
time measurements.
Alternate Horizontal Display Mode
In this mode, both the A Intensified Sweep and the B
Delayed Sweep traces are displayed. The mode is entered
by first entering the A Intensified Horizontal Display mode
(PULL-INTEN) then setting the B SEC/DIV switch to a
faster sweep speed than the A SEC/DIV switch setting. The
length of the intensified-zone display now becomes a
function of the B Sweep speed. Increasing the B Sweep
6-7
Figure 6-8. Small-angle phase difference.

Tektronix 2445 Specifications

General

Brand	Tektronix
Model	2445
Category	Test Equipment
Language	English