Guralp’s range of short period seismometers are designed for monitoring earthquakes in your local region, typically within about 500km of the sensor. The closer you are to an earthquake, the more high-frequency signals you can see, so with a range of 1-100Hz, the CMG-6T-1 is the ideal sensor for this application. Most of the stations in the SRC observatory network use this sensor connected to a Kelunji recorder.
The CMG-6T (data sheet) is also available with extended low frequency range to detect signals from more distant earthquakes. The CMG-6T comes with a frequency range of 30-seconds to 100Hz. The CMG-6 range of instruments have an aluminium chassis, making them light and very portable.
If you only need a vertical (not triaxial) sensor, the CMG-6V is also available in 1 and 30 second response versions.
The Guralp CMG-40 range of sensors have similar characteristics to the CMG-6 range, but have a stainless steel chassis for use in more corrosive environments (e.g. high humidity coastal areas). In addition to 1 and 30 second versions, the slightly lower noise of the CMG-40T also allows the option of a 60-second long period response. A CMG-40V is also available.