CMG-DM16
CMG-DM16 (both variants) front panel
The CMG-DM16 16-bit digitiser module is housed in a standard 19" rackmount enclosure, with individual inputs channels accessed through BNC connectors. is particularly useful for converting legacy equipment and environmental signal sources for use with modern communication systems.
CMG-DM16-R8
CMG-DM16-R16-DCM
Features
- 8 low noise 16-bit ADCs (16 in the CMG-DM16-R16-DCM version)
- Multiple selectable output rates from 200 to 1 sample/s
- STA/LTA and level triggering
- Simultaenous triggered and continuous outputs
- Synchronised UTC timestamped data using a single low power GPS module
- CMG-DM16-R16-DCM only — Internal DCM module with Linux OS, web server and secure shell access
Specification
| Seismic channels | ||
|---|---|---|
| Inputs | ±10V differential with transient protection | |
| Input impedance | 1MΩ, 10nF | |
| Common mode rejectection | 100dB at 50Hz | |
| GPS | ||
| External GPS (CMG-GPS2) | GPS can be connected with up to 50 metres of cable | |
| GPS Power | Supplied via the GPS connector on the digitiser | |
| GPS Time Format | NMEA | |
| Digital signal processor | ||
| Type and speed | M56002 running at 20MHz | |
| Hardware sampling rate | 2KHz | |
| Selectable sample output rates | Up to three separate rates are available concurrenly, starting at 200sps and dividing by 2, 3, 4, 5, 8 or 10. | |
| Anti-alias filters | 3-pole | |
| Low pass filters | FIR | |
| Out of band rejection | 140dB | |
| In band ripple | -140dB | |
| Digitiser performance | ||
| Standard output format | 16-bit | |
| Noise-free resolution, NPR | 17.5 bits at 5sps | |
| Absolute accuracy | Standard 0.5%, optional 0.1% | |
| ADC Type | Successive approximation | |
| Clock | ||
| Oscillator | Standard 800ppb, optional 50ppb (oven controlled) | |
| Interface for external receiver | GPS | |
| Sync for external receiver | < 200ms | |
| Power | ||
| Input power supply | +12V to +36V DC | |
| Current at 12V DC | 250mA | |
| Physical dimensions | ||
| Rackmount | standard 19" width, 1U for CMG-DM16-R8 or 2U for CMG-DM16-R16-DCM | |
| Width | 437mm | |
| Height | 42mm (CMG-DM16-R8) or 84mm (CMG-DM16-R16-DCM) | |
| Depth | 305mm | |
| Output options | ||
| RS232 | 100ft | |
| RS422 | 500ft | |
| Ethernet | 10-Base-T ethernet (only in CMG-DM16-R16-DCM version). | |