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PC27E
6.6.2 Aliasing
Never try to sample a signal at a rate less than or equal to twice the signal frequency.
Otherwise distortion known as aliasing will arise where the frequency of the sample data will
appear to be much less.
Aliasing is illustrated in the following diagram.
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6.6.3
Inherent Offset in ±4 Volt Bipolar Mode
There is no facility to adjust the offset to zero in ±4 volts, bipolar mode. This gives rise to a
possible offset error of a few millivolts on this range.
If necessary the offset could be compensated in software by subtracting the offset value from
each sample data.
6.6.4
Multiplexer Inputs
Please note that all unused analog input channels must be grounded. The maximum signal
voltage applied to any multiplexer input must not exceed ±5 volts.
6.7
Calibrating the PC27E
6.7.1
Unipolar Calibration
1.
Run the PC27E Pascal demonstration program
2.
From the main menu, press 2 to select Software Controlled sampling on one channel
only .
3.
Enter 1
for unipolar Input and confirm.
4.
Enter 1 for the channel number. (Note in the Pascal demo program, the channels are
numbered 1 to 16).
Содержание PC27E
Страница 23: ...PC27E Page 23 FIG 7 PC27E PRINTED CIRCUIT BOARD LAYOUT...
Страница 24: ...Page 24 PC27E FIG 8 PC27E CIRCUIT DIAGRAM...
