SIO L-Cheapo

SIO L-CHEAPO Active-Source/Rapid Response OBH/S

Drawing of the SIO L-Cheapo active source/rapid response instrument. The data logger used in this instrument is identical to that used for the wideband seismometer and is fully interchangeable. The flotation for both instruments consists of 13" glass balls. The sensors are hydrophones and 2 Hz vertical geophones although a Differential Pressure Gauge (DPG) can be substituted for the hydrophone. The package can be deployed as a single channel moored instrument as well in a hydrophone/DPG-only configuration. The recording duration is increased by approximately two months in this mode. Both a flashing light and a radio beacon are used for recovery. The acoustic release alternately fires one of two available burnwires for release.

(Click on Figure for a full size version in a separate window)

Technical Specifications: SIO Active-Source/Rapid Response OBH/S

Or

Low-Cost Hardware for Earth Applications & Physical Oceanography

(L-CHEAPO)

Seismometer Mark Products L22 2 Hz vertical-component geophone mounted in separate pressure case.

Pressure Sensor HiTech HYI-90-U hydrophone with internal preamp. Bandwidth (-3 dB) is 50 mHz - 15 kHz.

Digitizer L-CHEAPO 24-bit A/D. Dynamic range at 31.25 s/s is 130 dB and at 250 Hz is 124 dB. Uses the Cirrus/Crystal Semiconductor chip set CS5321-CS5322 - same as IRIS/PASSCAL

Sample Rates 1 kHz (1 channel), 500 Hz, 250 Hz, 125 Hz, 62.5 Hz, 31.25 Hz.

Clock Seascan Precision Timebase. Drift rate is 1:3-5 x 10-8 (<0.5 ms/day before correction and <0.1 s/yr after correction)

Disk Capacity 9 GB hard disk

Data Offload SCSI transfer of data can be done through the end cap without opening the pressure case for experiments in which rapid deployments are necessary.

Battery Pack Batteries are mounted in the data logger pressure case. Separate batteries power the acoustic release.

Recording duration Lithium battery pack can provide power at 31.25 Hz for 9 months or at 250 Hz for 4 months (6.4 months compressed). Rechargeable NiCAD batteries can provide power for experiments with durations of no more than 5 days.

Weight 280/200 lbs with/without anchor

Pressure Case 7" diameter Al cylinder

Release Double burnwire operated acoustically

Dimensions 36" high x 26" x 38"

Power 385 mW (or 335 mW compressed) at 125 s/s and 540 mW (or 440 mW compressed) at 250 s/s for 2 channels.

Technical Specifications: SIO Active-Source/Rapid Response OBH/S Or Low-Cost Hardware for Earth Applications & Physical Oceanography (L-CHEAPO)
Seismometer	Mark Products L22 2 Hz vertical-component geophone mounted in separate pressure case.
Pressure Sensor	HiTech HYI-90-U hydrophone with internal preamp. Bandwidth (-3 dB) is 50 mHz - 15 kHz.
Digitizer	L-CHEAPO 24-bit A/D. Dynamic range at 31.25 s/s is 130 dB and at 250 Hz is 124 dB. Uses the Cirrus/Crystal Semiconductor chip set CS5321-CS5322 - same as IRIS/PASSCAL
Sample Rates	1 kHz (1 channel), 500 Hz, 250 Hz, 125 Hz, 62.5 Hz, 31.25 Hz.
Clock	Seascan Precision Timebase. Drift rate is 1:3-5 x 10-8 (<0.5 ms/day before correction and <0.1 s/yr after correction)
Disk Capacity	9 GB hard disk
Data Offload	SCSI transfer of data can be done through the end cap without opening the pressure case for experiments in which rapid deployments are necessary.
Battery Pack	Batteries are mounted in the data logger pressure case. Separate batteries power the acoustic release.
Recording duration	Lithium battery pack can provide power at 31.25 Hz for 9 months or at 250 Hz for 4 months (6.4 months compressed). Rechargeable NiCAD batteries can provide power for experiments with durations of no more than 5 days.
Weight	280/200 lbs with/without anchor
Pressure Case	7" diameter Al cylinder
Release	Double burnwire operated acoustically
Dimensions	36" high x 26" x 38"
Power	385 mW (or 335 mW compressed) at 125 s/s and 540 mW (or 440 mW compressed) at 250 s/s for 2 channels.