Geometrics Memory-Mag G-856AX, Руководство по эксплуатации

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Geometrics, Inc
.
G-856AX Operation Manual
49
and/or the 3-reading average so it is best to use alkaline batteries, rechargeable batteries
or external power when these functions are enabled.
SWITCH 5 - DISPLAY OFF AFTER 5 MINUTES AUTO CYCLE
If Switch 5 is turned ON, the display will blank if the keyboard is not exercised for five
minutes. When you first set up the instrument, the display will light for five minutes to
allow initial monitoring of the operation, but after you leave and those minutes have
elapsed, the display will shut down to save power. If Switch 5 is OFF, the display will
continue to light with each measurement cycle.
Switch 5 is applicable to the AUTO mode. On some occasions it will be desirable to have
the measurements displayed as they automatically acquired. Such an occasion would be
during surveys where the operator wishes to record automatically and also wants to
monitor the data values. The AUTO mode is normally used for base station operation and
here there is usually no reason to display the measurement values because the
magnetometer is running unattended.
SWITCHES 6, 7, AND 8 (BAUD RATE)
Switches 6, 7 and 8 are used to set the baud rate. The RS-232 interface will output data at
selected speeds (baud rate). Different types of devices can send and receive at different
rates or combinations of rates. A mechanical Teletype with an RS-232 interface will
receive at 110 baud. A standard telephone line with a modem will communicate at 300
baud or higher. Printers with RS-232 interfaces may handle 300 baud and higher.
Computers can accommodate data transmission at 9600 baud and higher. The storage or
printing device that you connect to the G-856AX will either have a specified baud rate or
a selection of baud rates. You will want to use the fastest combination that is common to
both the magnetometer and external device but the baud rate setting must be the same on
both devices.
The data transfer rate in characters per second is approximately one/tenth the baud rate. A
reading contains about 30 characters and includes FIELD, TIME, STATION NUMBER,
DAY, LINE NUMBER, spaces, punctuation marks, carriage returns, line feed, and some
null characters to allow time for a printer return to the start of a new line. This means that
a single reading will require as much as three seconds to print on a slow telex machine, or
as little as I/5 of a second to transfer to a computer.
Internal Reset switch
There is a small red and white push button reset switch in between the circuit boards on
the left hand side of the instrument chassis. The location of this switch is shown in
Figure 23. In the event that the magnetometer’s processor is not responding it may be
necessary to reset the G-856AX. Care should be taken when using this switch as all data
in memory and all internal settings such as the Clock and Cycle times will be reset to
default settings. Make sure you attempt to download the data prior to using this switch.