Tv Line Signal; Tv Field Signal; Dela Yeo-Sweep Magnification - Tektronix 2230 Operator's Manual

The frequency of the unknown signal is then calculated:
1
Frequency
= - - - =
2.083 kHz
480
µS
TV LINE SIGNAL
The following procedure is used to display a TV Line
signal:
1. Preset instrument controls and select the A
TRIGGER mode of P-P AUTO/TV LINE.
2. Apply the TV signal to either vertical-channel input
connector and set the VERTICAL MODE switches to
display the channel used.
3. Set the appropriate VOL TS/DIV switch to display
0.3 division or more of composite video signal.
4. Set the A SEC/DIV switch to 10
µS.
5. Set the A TRIGGER SLOPE switch to either OUT
(for positive-going TV signal sync pulses) or IN (for
- - negative-going TV signal sync pulses).
NOTE
To examine a TV Line signal in more detail, either
the X10 Magnifier or the Delayed-Sweep
Magnification feature may be used.
TV FIELD SIGNAL
The television feature of the instrument can also be
used to display TV Field signals.
1 . Preset instrument controls and obtain a baseline
trace.
2. Set the A TRIGGER Mode switch to TV FIELD (P-P
AUTO and NORM buttons both pushed in) and set the A
SEC/DIV switch to 2 ms.
3. To display a single field, connect the TV signal to
either vertical-channel input connector and set the VERTI-
CAL MODE switch to display the channel used.
Basic Applications-2230 Operators
4. Set the appropriate VOL TS/DIV switch to display
2.5 divisions or more of composite video signal.
5. Set the A TRIGGER SLOPE switch to either OUT
(for positive-going TV signal sync pulses) or IN (for
negative-going TV signal sync pulses).
6. To change the field that is displayed, momentarily
interrupt the trigger signal by setting the AC-GND-DC
switch to GND and then back to AC until the desired field
is displayed.
NOTE
To examine a TV Field signal in more detail, either
the X10 Magnifier or the Delayed-Sweep
Magnification feature may be used.
7. To display a selected horizontal line, first trigger the
sweep on a vertical (field) sync pulse, then use the
"Magnified Sweep Runs After Delay" procedure in this
part (steps 5 through 7) to magnify the selected horizontal
line for a closer examination. This procedure is useful for
examining Vertical Interval Test Signals (VITS).
8. To display either Field 1 or Field 2 individually, con-
nect the TV signal to both CH 1 and CH 2 input connec-
tors and select BOTH and ALT VERTICAL MODE.
9. Set the A SEC/DIV switch to a faster sweep speed
(displays of less than one full field). This will synchronize
the Channel 1 display to one field and the Channel 2
display to the other field.
DELA YEO-SWEEP MAGNIFICATION
The delayed-sweep feature of the instrument can be
used to provide higher apparent magnification than is pro-
vided by the X10 Magnifier switch. Apparent magnification
occurs as a result of displaying a selected portion of the A
trace at a faster sweep speed (B Sweep speed). The A
SEC/DIV switch setting determines how often the B trace
will be displayed. Since the B Sweep can occur only once
for each A Sweep, the A Sweep time duration sets the
amount of elapsed time between succeeding B Sweeps.
The intensified zone is an indication of both the location
and length of the B Sweep interval within the A Sweep
interval. Positioning of the intensified zone (i.e., setting the
amount of time between start of the A Sweep and the
start of the B Sweep) is accomplished with the B DELAY
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