GSB User Manual
GSB User Manual (593-01940-01 Rev C)
release date: TBD
Page 22 of 27
measured voltage is correct. The results are reported as the percent error
for each expected 2:1 gain step. Test specifications are in Table 2.
Table 2: GSB Gain Accuracy Instrument Test
Dynamic Range
: This test measures the signal to noise ratio of the
seismic channel. Two records are required for this test. The first record
sets the input switches to the internal resistor’s position with no test
oscillator and is used to compute noise value. The second record sets the
input switches to the test oscillator position, and the test oscillator is set
to run at 31.25Hz at full scale and is used to compute the RMS value of
the full scale data. The ratio of RMS value of the full scale data to noise
is computed to yield the dynamic range of the data channel. Test
specifications are in Table 3.
Table 3: GSB Dynamic Range Instrument Test
Impulse
: The impulse test compares the internal impulse response for
each channel with a reference impulse trace. The input switch is set to the
test oscillator and a ½ sample width impulse is generated every second at
amplitude of 80% of full scale. The final 2048 samples of a data record
are examined. The difference in amplitude with the reference is