Minicom Advanced Systems CMG-DCM manual Tap # Rate Bandwidth Samples/s

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Operator's guide

some channels, you should uncheck Common values before altering them.

If you are using Scream!, you can use the Control window to change the values of the STA and LTA periods, together with the Ratio, without restarting the digitizer. See the documentation for Scream! for more details.

Since it is not generally advisable to trigger from broadband data, the digitizer provides a set of standard bandpass filters to apply to the data streams before they are tested for the trigger condition. This filtering serves to maximise sensitivity within a the frequency band of interest, and filter out noise outside this band. You can select which bandpass filter to use from the Trigger filter drop-down menu. The corner frequencies of the pass band of the filter are determined by the Nyquist frequency, which is given by the sampling rate of the triggering data. The three filter options have pass bands between 10 % and 90 %, between 20 % and 90 % and between 50% and 90% of the data’s Nyquist frequency, respectively.

The possible filter configurations are shown in the following table:

Tap #

Rate

Bandwidth 1

 

Bandwidth 2

Bandwidth 5

(samples/s)

 

 

(Hz)

 

 

 

(Hz)

 

(Hz)

 

 

 

 

 

 

 

0

200

10 – 90

20 – 90

50 – 90

1

100

5 – 45

10 – 45

25 – 45

 

50

2.5

22.5

5

– 22.5

12.5

– 22.5

 

40

2 – 18

4

– 18

10 – 18

 

25

1.25 – 11.25

2.5

11.25

6.25

– 11.25

 

20

1 – 9

 

2

– 9

 

5 – 9

 

2

50

2.5

22.5

5

– 22.5

12.5

– 22.5

 

25

1.25 – 11.25

2.5

11.25

6.25

– 11.25

 

20

1 – 9

 

2

– 9

 

5 – 9

 

 

10

0.5

4.5

1

– 4.5

2.5 – 4.5

 

8

0.4

3.6

0.8

3.6

2 – 3.6

 

5

0.25 – 2.25

0.5

2.25

1.25

– 2.25

 

4

0.2

1.8

0.4

1.8

1 – 1.8

 

2

0.1

0.9

0.2

0.9

0.5 – 0.9

3

25

1.25 – 11.25

12.5 – 11.25

6.25

– 11.25

 

10

0.5

4.5

1

– 4.5

2.5 – 4.5

 

5

0.25 – 2.25

0.5

2.25

1.25

– 2.25

 

4

0.2

1.8

0.4

1.8

1 – 1.8

 

 

 

 

 

 

 

 

 

 

 

December 2005

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Contents CMG-DCM Table of Contents December Inside the DCM Introduction CMG-DCM Inside the DCM Network services Serial port servicesSee .4, Connecting to a local network for full details Power supply Installing the CMG-DCMOverview Connecting over a serial link Connecting to a single computer192.168.0.x Connecting over EthernetConnecting over USB Using an internal modemConnecting to a local network Gcfgdbset option-namenew-value Connecting to the Internet Wi-FiSetting up the CMG-DCM Connecting digitizers and external hardwareWeb setup Setting up digitizers Using Scream General notes UsageDCM as a data store Gnblocks port-number Page CMG-DCM DCM as a GCF data source Accessing the DCM command line through gcfout Sensor arrays DCM as a network data hub Communicating with digitizers Configuring digitizers Data storage and retrieval Using miniSEED format Real-time data transmission CD1.0 and CD1.1 Troubleshooting DCM installations Cannot connect to the DCMs Scream! server Cannot see the DCMs Web site over Http or HttpsCannot Gcfping the DCMs Scream! server DCM is not receiving any data streams Can Gcfping the DCMs Scream! server, but no data appearsDCM is receiving streams, but they do not contain any data Use the Serial port configuration → port name Web page, or143032 up 34 min, load average 1.24, 1.32 General Configuration optionsDisk CMG-DCM Serial port configuration CMG-DCM Page Ethernet port Network configurationStatic routes DNS setup Incoming mail setup Outgoing mail setup Remote access Administrators PPP Mgetty Scream Data transferAutoDRM Scream! ClientHttp client Http serverCD1.0 CD1.1 CD1.1 subframe configuration DSS Server configuration Seed Page CMG-DCM Data Viewer ActionsStream list Icon barDigitizer Setup General digitizer settings Digitizer output control CMG-DCM Trigger criteria CMG-DCM Tap # Rate Bandwidth Samples/s Auxiliary Mux channels Sensor mass control Partition, and format disk Disk toolsCheck disk filesystem Flush flashCamera Disk filesRecent Log Entries Summary Network configurationData Out Port, Serial Port A, Serial Port B DNS configurationTamper lines Flash StatusDisk Status Software Versions Inside the DCM File systems CMG-DCM Command line tools Configuration Digitizer console access Data flow MonitoringDigitizer status Tamper lines Over the Internet Updating the DCMFrom the hard disk Removing support packagesFirmware Libgconfigdb Appendix A.1 Modular DCM units Appendix a Connector pinoutsPort a and B Data OUT portNetwork connector USB connectorDM/AM module output Appendix A.2 Integrated DCM unitsAppendix B.1 Sensor response codes Appendix B Sensor and digitizer typesDigitizer Appendix B.2 Digitizer type codes