Guralp Systems CMG-DCM - Manual (Page 93)

Operator's guide
•
a SEED location name for the instrument (or leave blank to have
the DCM generate one automatically);
•
a SEED channel name for the stream (or leave blank to have the
DCM generate one automatically);
•
a case-sensitive code for the sensor type (see Section 10.1, page
130);
•
a case-sensitive code for the digitizer type (see Section 10.2,
page 131)
•
the sensitivity of the sensor, prefixed with a V for a sensitivity in
V/m/s, or A for a sensitivity in V/m/s
2
(in the example, around 1
V/m/s).
Note that the unit follows directly after the sensitivity, with no
colon.
The sensitivity is given on the sensor's calibration sheet. The
sensitivity of a sensor integrated with a digitizer is quoted as a
single-ended sensitivity, whilst stand-alone digitizers are
provided with their differential sensitivity. A differential
sensitivity is quoted as, e.g. 2 × 3000 V/m/s. In this file, you
should use the doubled value, i.e. 6000 V/m/s, for a stand-alone
digitizer. For integrated digitizers, you should use the single-
ended value quoted.
•
the sensitivity of the digitizer, in volts per count (here 1.6 × 10
-7
V/count = 0.16 V/count). This is given on the digitizer's μ
calibration sheet.
•
the decimation sequence code. This is an integer between 0 and
239 which describes the sequence of filters in use by the
digitizer. If you have a recent digitizer (with firmware newer
than version 0.91) this information is included in the incoming
GCF streams, so you can leave this field blank. The codes
corresponding to each possible decimation sequence are
available from the support section of the Güralp Systems Web-
site.
When you have finished editing the file, clicking Save changes will
write the changes to disk. The changes will not take effect, however,
until the SEED service is restarted.
To restart the SEED recorder, browse to the Tools – Process Overview
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