Geometrics G-877, Руководство по эксплуатации

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Auto tuning is not recommended if large changes in the field are anticipated, such as those
associated with steel target location. The limits on the
span of autotuning should be set close to
the local field (i.e., ± 10K ) when the auto tuning is employed. The manual tuning uses strings
in the form of:
T531<enter> meaning tune to 53,100 gammas
TA<enter> to enable auto tuning:
If you are in HYPERTERMINAL, you also can re-tune in this way. To send the tuning
manually, press "T". You must use upper case letters. Wait for the magnetometer to echo the
"T", then press the next character and wait for an echo and so on. The magnetometer assumes
that the first digit it gets is the tens of kilo gammas the next the kilo gammas and third hundreds
of gammas. All three digits must follow the "T" code. After the three digits are echoed, press
enter. If you make an error, press "T" to restart the entry procedure.
4.5.3 Transmitted Data Format:
The data transmitted from the magnetometer has the following line format: [factory set - field
changeable]
magnetometer value - signal level -depth- tuning - input voltage
MagLogLite™ defaults to assuming the preamble string is the "=" sign that is transmitted but
not displayed. This string marks the start of the line of text that is the data so that the manual
tuning information does not get confused with the data. After the preamble comes the data item
selected by the user to be sent first, then the second, third, and so on until all selected values are
displayed. This is followed by the post amble string. In the post amble string there will be a
"\N" to cause a carriage return/line feed pair to be sent.
The formatting of the numbers is controlled by strings of pound signs (#) and optionally a
decimal point (.). If the format is in the form "###.##" this would mean three digits before the
decimal and two after. Only those digits specified in the format will be transmitted, e.g., if the
field is 51234.56 and the field format is set to "###.#", then the value sent will be 234.5.
The total field reading is transmitted after conversion to nT (gammas). The A to D Converter
values are scaled to a conventional unit of measure before transmission. For example, Volts
(input DC voltage) and the signal strength presented in arbitrary units. Typical signal levels of
300-500 units can be expected depending on the direction of tow and local field strength. The
signal strength scaling is fixed and can not be changed.
Status Codes:
0 I'm OK
1 Unexpected 'R' received
2..9 Reserved for other minor errors
11 Counter 1 failed
40 G–877 MARINE MAGNETOMETER OPERATION MANUAL