3.  Abbreviated Seismic Research Observatory - ASRO:  [ AS ]

DATES OF OPERATION:  	09 Oct 1976 to 27 Sep 1987 

SEISMOMETER TYPE
A three component set of Geotech long period seismometers (S-12 horizontals and a
S-11 vertical) with a period set at 30 seconds are installed inside a sealed tank which is 
filled with with argon gas.  The short period vertical component is obtained from a Johnson 
Matheson Model 6480 seismometers.

DIGITAL FORMAT:
16 bit gain-ranged data words for all components.  Range: +2,096,1128 to -2,097,152 counts.

EVENT DETECTOR ALGORITHIM:  
The Murdock event detector (Murdock 1983) was installed on 03 May 1983. Prior
to that time a detector developed for the SRO/ASRO systems by the Unitech Corp.,
Austin, Texas was used.  This detector was not documented.

Click on any of the following items for further information.

• Channel Data
• Amplitude Response to Ground Velocity
• Seismic Noise Study graph information

• Seismic Noise Level - Annual
• Seismic Noise Level - Seasonal/Diurnal

COMMENTS:
All of the ASRO have the same format and the same response as the SRO systems.  The
digital recording system and the software are identical to the SRO.  The seismometers and
amplifiers are the same as the HLGP.  All ASRO stations are HGLP stations that have been 
upgraded to SRO equivalent.