_REVISION - C1996083 ‎(2)‎

• Permit No: C1996083
• IBM Index Class Name: REVISION
• Doc Name: Seismic Event Data Acquistition and Processing Distribition and Coordination Across PC-Based Network
• Type & Sequence: PR10
• Media Type: D
• Archive: No

Table 1—Commercially available A/D converter hardware
Model Numberof Nominal Interface Operating Manufacturer
channels resolution system
(bits)
Par4ch 4 24 Parallel Lin., Symmetric
Par241b 8 24 Parallel W9x/NT, Research,
DSPA64 64 16 ISA DOS Kirkland,WA
DT2824 16 12 ISA DOS Data
DT-EZ 16 11 ISA Translation,
DT2821 16 12 ISA Marlboro, MA
The data acquisition software XRTP was developed for Dam Translation boards through
IASPEI (Lee, 19941 and requires the DOS operating system. The RTPSR (TottCo) software for
the Symmetric Research DSPA64 A/D converter is similar. Executable and source codes ac
provided for Par24b and Par4ch boards so that the user can implement his/her own triggering
criteria and make other customizations. In all cases, data files are either output directly in PC-
SUDS format or they are immediately converted to this format.
(1) Remote .signal digiliaing and wireless data transmission to a network computer. Low-
power, custom-built, three-channel 16-bit A/D converters are used to digitize signals at or near
remote sensors. Maximum sampling rate is 1,000 samples per second per channel. Data are
continuously sampled and transmitted back to a data acquisition computer via a 115.2 kbaud
wireless serial telemetry link. Data are telemetered over line-ofsight distances of several
kilometers using pairs of license-free 9004MHz and/or 2.4-151+z frequency-hopping, spread-
spectrum radio transceivers. The data are received by a network PC that is equipped with a 16-
channel serial port board and running a modified version of IASPEI's XRTPDB software (Lee,
1994).
(3) Loin-power remote PC-104
systems with wireless networking.
Current development work focuses
on the use of low-power, network-
___ . ready, PC-104 format computers
F7p (Figure 2) as a basis for stand-
: alone data acquisition platforms.
Four- or eight-channel, 24-bit
Digitizing units connect to the
parallel port and sample the data at
1.000 samples per second or
higher. Sensors are deployed in
_ small cabled arrays in specific
geographic domains (e.g., mesa
top, canyon bottom, etc.). Power is
supplied from 12-V do solar panels
Figure 2. PC-104 remote, Linux-based,seismic data
acquisition computer.
Mention of specific products or manufacturers does not imply endorsement by the National Institute of
Occupational Safety and Health.