Peak Voltage Measurement - Tektronix 2247A Operator's Manual

·. ,o
Basic Applications
Some features of the CH 1 /CH 2 Voltmeter function are:
a. Measures CH 1 or CH 2 while viewing either channel. ( Select the
measurement source channel using the SET MEAS' MT CHANNEL
menu.)
b. Measures signal levels (DC values and peaks) In SGL SEQ (slngle-
sequence) Trigger MODE continuously. (Use CONFIGURE function
In the Service Menu to get menus and readouts
tt!>
remain on
between single sequence triggers. )
c. Finds peaks of signal applied, not only just the displayed portions of
the waveform.
d. Defines a portion of the waveform (GATED measurements-
especially useful for making measurements on a multi-level signal)
on which to make the selected measurement. ( Use page 2 of the
VOLTMETER menu to select a GA TED-measurement mode.)
NOTE
Very narrow-gated measurements at 20 ns per div sweep
speed are impractical due to imprecise definition of the
Intensified zone at that sweep speed.
Peak Voltage Measurement
To make a +peak voltage measurement use the following procedure:
1 . Apply the signal to be measured to CH 1 Input conne~tor.
2. Set:
VERTICAL MODE
Horizontal MODE
3. Press AUTO SETUP button.
CH 1
A
4. Press the VOLTMETER CH1 /CH2 button to call up the selection menu
and select the +PEAK choice. Any of the page one choices may be
selected as required for the waveform measurement wanted.
Depending on the way the CONFIGURE choices of the SERVICE menu
have been made, the menu will either go off when the measurement
selection Is made or It will stay on. If the menu remains on, press the
CLEAR DISPLAY button once to remove It from the display. See the
SERVICE Menu discussion In Section 3 for further details.
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2247 A Operators
Basic Applications
NOTE
The TRACK MEASMT cursor may be displayed with the
waveform. Pressing CLEAR DISPLAY in the Initial setup re-
moves the measurement tracking cursor from the display
(and also cancels the measurement) but does not disable
the feature once it has been enableq; the next time a
CH 1 /CH 2 Voltmeter measurement mode Is called for, the
measurement tracking cursor Is again displayed.
5. Press the CURSOR VOL TS button and display page 2 of the menu by
selecting the (TO AUTO TRACKING MENU) choice. Of the three
features available In page 2, select both TRACK MEASMT and TRACK
rh.
Menu labels are UNDERLINED when the function Is enabled. The
TRACK
rh
cursor Is especially useful for ptovlding feedback to the user
about de offset of the signal from ground l~yel.
NOTE
In this menu, the se(ect buttons toggle the choices on and
off with each press, and all three choices may be selected
(but not all displayed together because only two cursors are
~/lowed). Also, pressing CLEAR DISPLAY (as many as three
times may be necessary) does turn off tl1e TRACK TRIG LVL
and TRACK
rh
choices.
6. Press either MENU OFF (In the menu selection list) or'CLEAR DISPLAY
(once) to remove the AUTO TRACKING menu from the display.
NOTE
If VOLTMETER PK-PK measurement' is selected, two
TRACK MEASMT cursors are requirf3d; therefore, the
TRACK
rh
cursor will not be displayed.
7 . See Figure 5-1 . The test signal used for the example has a de offset
(as shown by the position of the TRACK
rh
cursor) and +PEAK value
( peak ac + de) as Indicated by the voltage readout.
2247A Operators
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