Maximum deviation in volts
2
100%
10 volts
× ×
The maximum deviation must be less than
±
2.5 mV in order to meet the
±
0.05%
specification.
As the input is decreased, the amplifier gain should remain constant (OUTPUT should
decrease linearly); whether or not it does is tested by comparing the OUTPUT to a sig-
nal known to decrease linearly with the amplifier input; the pulser’s direct OUTPUT
meets this requirement since it is related to the amplifier input by a passive attenuator.
The factor of two must be included because the summing network also serves as a
voltage divider decreasing the apparent deviation by a factor of two.
Note that nonlinearity and instability in the pulser OUTPUT do not enter into the mea-
surement, because both direct and attenuated outputs will be affected identically, save
for negligible effect of the pulser’s attenuator instabilities over the short time period
required for the test. Instabilities in the baseline level on the oscilloscope null point
equal with the baseline. The oscilloscope are due to oscilloscope triggering, dc level
fluctuations and noise, and need not be of concern in this test.
SCA Operational Checks
If the SCA section of the 2015A needs to be recalibrated, it is strongly suggested that
the unit be sent back to the factory.
Setup
1.
Set the 2015A controls as follows:
LOWER LEVEL:
1.0
WINDOW:
12
LLD (J5):
INT
SCA MODE (J6):
TSCA
DISC A (J7):
ULD
DISC B (J8):
OUT
∆
E RANGE:
10
COARSE GAIN:
4
FINE GAIN:
MAX
SHAPING:
2
µ
s
27
SCA Operational Checks
Summary of Contents for 2015A
Page 1: ...Model 2015A Spectroscopy Amplifier Timing SCA User s Manual 9231694B 01 05...
Page 6: ...Notes iv...
Page 12: ...Internal Controls 6 Controls and Connectors Figure 4 Internal Controls...
Page 55: ......
Page 56: ......
