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  •  What is a seismometer?
  •  What types of educational
      seismometers are available?
  •  How do I obtain a seismometer?
  •  AS-1 Assembly and Installation guide
  •  Displaying your station in realtime
  •  AS-1 Calibration and tune-up guide
  •  AS-1 Troubleshooting guide

What is a seismometer?

A seismometer is a very sensitive instrument that can detect movements of the Earth's surface. The surface is in constant motion due to natural and man-made phenomena. For example, the solid Earth tide is the stretching of the Earth due to the gravitational pull of the moon. Phoenix, Arizona slowly rises and falls twice a day about 40 cm due to the moon orbiting overhead. Mining explosions in Morenci, Arizona create seismic waves which shake Phoenix daily. The amplitude of these vibrations are less than a micrometer and the oscillations have a frequency of several Hz.

The wide variety of ground motion, both in terms of period of oscillation and amplitude of vibration make it impossible for a single seismometer to record all types of motion. The AS-1 seismometer is a simple inertial system that can detect local mining explosions as well as moderate or large earthquakes that occur globally.

The seismometer is called inertial because it is based on Newton's 1st Law: A body at rest will remain at rest. In the AS-1 seismometer a magnet is suspended by a spring from a boom. When the ground vibrates the boom moves, but the mass wants to remain at rest, so the spring is stretched. The relative motion between the boom and mass is proportional to the ground shaking and causes a tiny electric current to be generated that is sent to the seismograph to be converted into a seismogram. Unfortunately, the spring will eventually pull the mass, so the seismometer requires damping. Oil or a magnetic damping system is used to dampen the AS-1 Seismometer.


What types of educational seismometers are available?

AS-1 Seismometer

The AS-1 is a portable effective classroom tool for teaching about earthquakes and the instruments that record them. The AS-1 has been loaned to many teachers through the Seismographs in Schools program. The AS-1 electronics have recently been redesigned and production is currently underway!



The TC1 is a vertical seismometer with a natural period of approximately 1s.  Open-source hardware – based on the arduino uno -- boosts the longer periods in its recordings, so that teleseismic earthquakes are routinely detected, in addition to regional seismic activity. All plans for the TC1 and the interface between sensor and computer are freely available online to build your own, but the TC1 can also be purchased as a kit. Further information is available at


Raspberry Shake

Raspberry Shake (RS) is an easy to use, plug-and-play classroom seismograph compatible with jAmaSeis and SWARM educational software. Based on the popular “Raspberry Pi” computer, RS integrates sensitive Earth monitoring sensors with easy to use software. Teachers can access data from any RS in the world, making it a good solution for seismically active earthquake areas and quiet regions alike. Perfect for viewing micro-tremors and the larger events featured in IRIS Teachable Moments. Learn more on RS's social networks: TwitterFacebook and Instagram (@raspishake).



In the UK, the SEP seismometer system is a horizontal seismometer that uses electromagnetic induction to detect ground motion (velocity) and eddy current damping.


EAI S102

The S102 is an inertial seismometer that measures ground motion with respect to an elastically suspended mass.



Vertical School Seismometer, available commercially from Ward's Natural Science.



The CMG-PEPPV records vertical ground motion. It is a complex and sensitive instrument that can record global earthquakes.  Guralp seismometers are available from Guralp Systems.



How do I obtain a seismometer?

There are opportunities to include seismology in the classroom with or without a physical seismometer. Check out our Instructional Resources page for more information!

Instruments can be purchsed from the suppliers listed above, and IRIS resources are here to help get you started!

IRIS plans to begin selling AS-1 instruments again early in 2018, along with replacement electronics for the original "black box". 


AS-1 Assembly and installation guide

AS-1 manual

jAmaSeis software

Set of instructional videos that step through the assembly of the AS-1 educational seismometer.

Displaying your station in realtime

Many schools send a new image of their AS-1 helicorder record every 10 minutes to the IRIS Real-Time Seismic Image Display webpage.
Comparing ones own record to others is a very good way to deter­mine if a given signal is indeed an earthquake, as large events are always recorded by many stations. Variations in the background noise due to microseisms can also be monitored all across the country. And it is a wonderful way to share your seismometer im­ages with the community in which you live.

Your schools's helicorder images can be uploaded automatically to the IRIS real-time display pages using the jAmaseis software. If you have any problems getting set up, please let us know at


AS-1 Calibration and tune-up guide

Request a Calibration Kit

Your Name: 

Station Code: 


Shipping Address:

AS-1 Seismometer Calibration and Tune-up kits are available at no charge. They are available to any school in the US that is registered in our database. Not in our database? Register now!
  •  Enter your contact/shipping information in the request form.
  •  Also, download the guide to accompany the kit.
This kit and guide includes equpiment and instructions to perform 9 tune-up procedures to use when you set up, move, or just want the best performance possible from your instrument. Additionally, the guide includes the equipment and instructions to perform 5 calibration procedures.
Please use this guide to perform baselines tests so that if you have problems later they can be used to help troubleshoot your seismometer.


AS-1 Troubleshooting guide

Coming soon!