Keithley 3910 Operator's Manual page 22

S E r n O N
3
Operaf ion
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Figure 3-1. Model 3920 Front Panel
@
POWER ON/OFF
(Power
switch)
POWER controls AC power to the Model 3910.
Push t h i s switch up
td
turn
power on, and push
down to turn power off.
@
Display
The single-line 11-character display shows osdl-
a
lation
frequency,
parameter values, and other
important information during operation. An ac-
tive display also indicates
that
instrument power
is
turned on.
Push-button key
that
selects the parameter dis-
played to either oscillation frequency or GPB
address (only when GPlB option i s installed),
start/stop phase, mark wave number, and space
wave number. When
LED
at the lower left of the
*lay
is
lit oscillation frequency
is
selected.
When
LED
at the upper left of the display
is
lit
GPIB address, start/stop phase, and mark and
space wave numbers are selected.
DO^ VAR
m,
VAR (Square
wave
duty
wcle)
&h-button key to select either variable duty or
fixed square wave output. When LED in center
of key
is
lit variable duty is selected.
@
N ~ a r i a b l e d u g ratio
adjustment)
Rotating the variable duty adjustment knob d-
lows
you
to program the square wave duty cycle.
The allowed duty cycle ranges from 5% to 95%
under IOkHz,
and from 10% to 90% at lOlcHz to
100kHz.
I n the variable duty mode, the upper
frequency limit for square waves is restricted to
100mz.