Geometrics G-822A, Руководство по эксплуатации

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Geometrics, Inc. G-822/G-823 Magnetometer Manual
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Counter Number [0-2]:
Selects which counter the analog data will come from. Up to three daisy chained counters
may be logged by this program. The default is always counter 0 (the first [or only]
counter).
Analog Channel Number [0-5]:
Selects which A/D channel of the above counter is to be displayed. Do not confuse
"analog channel number" with "display channel number" above. They are not related in
any way. Think of the display channels as 6 separate input channels to a 6 channel analog
strip chart recorder. The counter channel numbers (along with counter number
information) specify a particular analog information channel. With three counters there
could be 18 separate information channels – any one of which could be configured to any
display channel. For instance, one analog channel could be assigned to two display
channels with differing full scale coefficients - allowing a course and fine graphics
display of the same channel.
The program does not ‘know’ which analog channels are actually coming out of
the counter. It is possible, for example, for the counter to be commanded to
output channels 0, 4, and 5 only. This program sees only three analog channels in
the counter's data stream and will refer to them as channels 0,1, and 2.
Unipolar/Bipolar [U/B]
As described in the magnetometer/counter manual there are 4 unipolar (including the
signal level) [0 to +4.096 volts], and 2 bipolar channels [ñ 2.048 volts]. This parameter is
used to signify which type of analog channel this is.
Clip/Wrap [C/W]
This parameter specifies what to do when the analog data exceeds the full scale setting
(see Full Scale Set below). Clip mode causes the data to be clipped at full scale so that
the channel traces the top of the display screen (or possibly the bottom of screen in
bipolar mode). Wrap allows the trace to over-scale and wrap back around to the bottom
or top of the screen.
Full Scale Set
Set the full-scale value of the display using the "+" and "-" keys. Note that a value of
10000 nT full-scale display as "0000" full scale. All other values display correctly in the
allocated 4 digits.