McVCO is a microcontroller-based frequency generator that replaces the voltage controlled oscillator (VCO) used in the analog telemetry of seismic data. It accepts low-level signals from a seismometer and produces a frequency modulated subcarrier suitable for radio or telephone links to a data collection site.
McVCO was designed for the purpose of improving the analog telemetry of signals within the Pacific Northwest Seismograph Network (PNSN). Its development received support from the University of Washington Geophysics Program, and both the Volcano Hazards and Earthquake Hazards programs of the United States Geological Survey (USGS).
This handbook covers operation of McVCO, provides a technical reference for those who require a closer look at how McVCO works, and covers a collection of topics that need explicit treatment or that spring from deployment of the instrument.