Channel 1 And Channel 2 Voltmeter - Tektronix 2247A Operator's Manual

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Operators Familiarization
number displayed channel for the delay time ( or B source 1 ) , and the next
lowest number displayed channel for the delta-delay time, ( or B source 2) If
more than one channel Is displayed. Both are set to the same channel when
only one Is displayed. CH 1 Is considered the lowest numbered channel, and
ADD Is considered the highest numbered channel.
NOTE
.
'
The last measurement Is initialized to If- SEC
•
I at power on
when the memory-backup battery is dead or has just been
replaced.
If
the battery is dead, refer the instrument to a
qualified service person to have It replaced.
Channel 1 and Channel 2 Voltmeter
Press VOLTMETER CH1 /CH2 button to display the first page of menu
choices. The selected measurement mode Is shown by an underlined menu
Item. Tracking cursors (measurement, ground, or trigger level) may be
displayed to show the measurement points on the displayed signal ( see
Conditions for Cursor Display) .
If a single channel ( CH 1 or CH 2) Is selected for display, It becomes the
def a ult measurement source channel. When neither channel is being dis-
played when a Voltmeter measurement Is selected, or recalled by the LAST
MEAS' MT button, CH 1 Is turned on as the default channel. If both CH 1
and CH 2 are being displayed, the default measurement source channel
upon each Initialization Is also CH 1. Use the SET MEAS' MT CHANNEL
function to assign CH 2 as the measurement channel. Turn off the CH 1
display If CH 2 Is the desired def a ult measurement source channel. If both
CH 1 and CH 2 are turned off whlle the Voltmeter measurement Is active,
the error message "VOLTMETER SOURCE: CH 1 OR 2 ONLY" will be dis-
played and the voltmeter measurement will be canceled.
Only one active measurement Is allowed at a time. The name of the active
measurement and measured value are displayed at the top of the screen. A
measurement Is canceled with no message when the Horizontal Mode Is
changed to a mode Incompatible with the active measurement mode. See
Table 3-1 In "Behavior for Horizontal MODE Changes" for compatible
modes.
If a +PEAK, -PEAK, or PK-PK Volts measurement Is selected when hori-
zontal mode Is either ALT or B, Cursor Knob Allocation Menu 1 Is displayed.
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2247 A Operators
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Operators Familiarization
MEAS
DELAY
Cursor Knob Allocation Menu 1
If MEAS Is selected from this menu, the Voltmeter measurement is
performed on an area of the A sweep that Is Intensified by the B sweep
display. The. Voltmeter measurement Is, In effect, gated by the B sweep,
with the gating Interval starting approximately at B sweep start
± (
0. 5
division + 20 ns) and ending approximately 11 divisions from B sweep start.
If measurement tracking cursors are enabled,·· they will track with the B
sweep display. The If- OR 'DELAY knob will control the B delayed sweep
position, even though the DELAY time Is no! displayed. When a Volts
measurement Is selected when B Trigger MODE Is not RUNS AFTER, an
error message "USE RUNS-AFJI!R-DELAY TRIG MODE" will be displayed,
and the Volts measurement will not start up. If B Trigger MODE Is changed
while a Volts measurement Is running, the Voltmeter measurement is
canceled, without a message, and the DELAY measurement runs.
,
If DELAY Is selected, the If- OR DELAY knob will control the B delayed
sweep position, and the DELAY measurement runs, displaying the delay
time value In the top line of the readout.
J
If horizontal mode Is changed to A when the above menu Is displayed, the
menu will disappear, but the selected Volts mea,surement will continue run-
ning, with the measurement tracking cursors tracking the A sweep ( as In
the normal, nongated version of the Volts measurement).
(VOLTMETER) DC
+PEAK
-PEAK
PK-PK
SELF CAL
(TO GATED MEASMT MENU)
(VOLTS PG2)
GATED +PEAK
GATED-PEAK
GATED PK-PK
(BACK TO PREVIOUS MENU)
Voltmeter and Gated Voltmeter Selection Menus
2247 A Operators
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