OPERATION
2-4
TEST CONDITIONS
DEFAULT CONDITIONS
If the back space key [<-] is held down while turning on the unit, it will be set to the default setup shown below
Any user calibrations are lost and factory calibrations are used.
Using [Recall] [0] [ENTER] will set the
unit to the conditions below
without
disturbing any user calibration values.
Parameter
AUTO
Frequency
1kHz
Drive Voltage
1.0V
Bias
OFF
Measurement Rate
SLOW
Averaging
OFF
Range Hold
OFF
Equivalent Circuit
SERIES
Display
VALUE
Trigger Mode
CONT
Binning
OFF
SETTING TEST CONDITIONS
Test conditions are set two ways. Most of the major test conditions are set using a direct key press. These
conditions have dedicated keys that change their values or settings. Other conditions are set through the
ENTRY display, including the number of averages, range, and relative values for deviation measurements. To
adjust these conditions, use the [Display] key to select the ENTRY display and press the key of the parameter
to be changed. A message indicating which parameter has been selected will appear on the left display and
the present value of the parameter will be shown on the right display. Input the new value using the numeric
keys and use the unit keys or the [ENTER] key to enter the value. Return to the desired display with the
[Display] key. If an illegal value is entered when changing the test conditions, the unit will beep and display
'rAnGE Error'. If this occurs the unit will disregard the entry and allow another value to be entered.
The [Calibrate] key is used to access a series of less often used functions. They are 'vtESt' (vernier test
voltage), 'SEttL' (settling time), 'nuLL cAL' (null or open and short circuit cal) and 'SELF tESt' (self test). To
access these functions, press the [Calibrate] key until the desired function appears. A message will appear
along with the present value of that parameter. The new value is entered in the same manner as with the
ENTRY functions.
FREQUENCY
There are five selectable frequencies for the SR720 (four for the SR715): 100 Hz,
120 Hz, 1.0 kHz, 10 kHz, and 100 kHz (SR720 only). The output frequency is
accurate to 100ppm (0.01%). Frequencies are set by pressing either the [UP
Arrow] or [DOWN Arrow] key in the FREQUENCY section until the desired
frequency LED is on. If the unit is in range hold on range 0, the 100 kHz
frequency is disabled. If 100 kHz is selected while in range 0, the unit will beep
and a
'r-f Error' (range - frequency error) will occur.
OUTPUT VOLTAGE
There are three primary output drive voltages that can be selected as well as a
verniersetting with 50mV resolution. The primary voltage levels are 0.10 Vrms,
0.25 Vrms and 1.0 Vrms. The vernier settings range from 0.1 Vrms to 1.0 Vrms.
The accuracy of the output voltage levels is 2 %. The primary output levels are set by pressing the [Select] key
until the desired output level LED is set. The vernier setting is programmed using the CAL menu. Press
[Calibrate] until the left display shows 'vtESt'. The right display will show the present output voltage. Although
the unit will accept 3 digits, it will round the entered voltage to the nearest 50 mV. When the output voltage has
