Here are some of the articles that have been recently posted to the PASSCAL website:

SmartSolo archives flipped polarity (IGU-16HR 3C 5Hz)

Dear EarthScope Community and EPIC PIs:

In September of 2023 we discovered that SmartSolo node (IGU-16HR 3C, 5Hz) data archived from EPIC experiments has a non-standard polarity on the Z-channel relative to the down-positive industry geophone convention. Details of this discovery and the steps that will be taken to correct this discrepancy, which will affect the existing and future archives, are outlined below.

Issue

The expected polarity for data archived from EPIC experiments are as follow:

Broadband seismometer – Up (Z-dip = -90), North and East motion produce a positive polarity. Geophone – Down (Z-dip = +90), North and East motion produce a positive polarity

Data archived, both PH5 and SEED, prior to October 05, 2023 from EPIC experiments using the SmartSolo nodes have the following polarity and metadata mismatch: 

Important Hardware/Software Notes for Researchers Using EPIC Equipment

This page includes important Hardware/Software Notes for Researchers Using EPIC Equipment. January 17, 2019: GPS Rollover

Late 2018 EPIC learned of a GPS week rollover event that can affect data logger performance and timing. EPIC has acquired a GNSS signal generator that can emulate GPS satellite signals. This satellite emulator allows us to test EPIC equipment that relies on GPS timing and to determine how equipment will handle the GPS rollover event. To date, we have determined that some models of GPS engines are affected by the rollover. How the rollover errors manifest is dependent on the data logger’s model and firmware version of the GPS engine.

Contacts

E-mail

Main EPIC mailing list: epic [dot] passcal [at] earthscope [dot] org

PI-Support and Logistics: epic [dot] logistics [at] earthscope [dot] org

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