
Scans by ArtekMedia © 2007
Overflow Conditions
The
RANGE
and
OFFSET
setup condition values for a given channel deter
mine the full range of acceptable input voltages for that channel. The
acceptable range is directly related to the boundaries of the recording area,
where
Upper Boundary
=
(RANGE)� (OFFSET)
Lower Boundary
=
(�RANGE)
�
(OFFSET)
If
any channel's input voltage exceeds the limits given by the channel's
upper and lower boundaries (as determined by the equations above), the
channel overflow indicator
will
turn on. Overflow conditions should be
corrected by making the proper adjustments to the range and/or offset
settings for the indicated channel. Data recorded during an overflow condi·
tion will be invalid, and the resulting plot
will
be clipped.
Displaying Input Voltages
The
Input Data-Display
FUnction
Inputsignal voltages may be digitized and displayed on the LCD by access·
ing the data display mode. This mode includes two different data display
functions, labeled
INPUT
and
PEN POSITION
on the right front panel. The
input data-display function is used to display input voltages, allowing the
HP
7090
to serve as a digital voltmeter. This function is often helpful in
determining the voltage range of input signals.
To obtain a voltage reading and observe digitized input on the display,
access the input data·display function by pressing the
DATA DISPLAY
selector
to light the
INPUT
indicator. Select the channel to be displayed by pressing
the appropriate Y-axis channel-select push button
(CHAN 1, CHAN
2,
or
CHAN
3).
Channel
1
is selected automatically
if
no other selection is made. The
lower, X-axis channel·select push buttons and indicators are disabled while
the input data-display function
is
in effect.
CHANNEL
SELECTED
FOR
DISPLAY
INPUT DATA D
I
SPLAY
FUNCTION ACCESSEO
. n
.' g
..
· U.
OISPlAYED
INPUT VOLTAGE
3-24
Measurement Setup Operations
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