Dmm - Tektronix 2465A Operator's Manual

Controls, Connectors, and Indicators
DMM
All DMM controls are momentary push buttons. The buttons alternately select
and deselect functions. Refer to Figure 5-8 for the location of items 58 through 70.
@
@
®
RANGE
Buttons
AUTO
UP and
DOWN
DC
VI
DC A
AC
V/AC A
dBV/dBm
dBV
Select full-scale ranges for measurements.
Selects autorange. The measurement range changes
as necessary to maintain the reading within 9% to
100% of full scale. Autoranging is automatically
selected each time a new measurement function is
selected. If auto ranging is active, pressing AUTO
deselects autoranging. When the button is pressed
again, autoranging returns.
When a measurement range changes, the display
blanks momentarily. If a measurement exceeds a
manually selected range or the highest range with
autoranging, "OVER" is displayed in the readout.
Change the measurement range. In autorange mode,
pressing either button disables autoranging and
selects the next range above or below the present
range. Pressing the UP button at the highest range
or DOWN at the lowest range does not change the
range, but changes the mode either from autoranging
to manual ranging or from manual to automatic. With
manual ranging, the display shows "MNL."
With manual ranging, measurements can exceed the
nominal full scale by 10%, except at the highest
range.
Turns the dc volts or dc amps function on or off.
Selects or cancels ac rms volts or ac rms amps.
Selects or cancels dBV or dBm.
Displays ac rms voltage measurements as the log of
the ratio of the input voltage to 1 V. Readings equal
20Xlog(VinputlVret)' where Vinput is the input voltage
and V ret is 1 V. With zero input, the readout displays
"OVER."
2465A/2455A/2445A Operators 5-27