A small indoor loop antenna captures the radio wave for amplification and rectification by the receiver. The SID station operates unattended until the end of each month. Recordings are then analyzed for the beginning, end, and duration of SID events. With computers becoming more available at reasonable cost, several SID program participants have switched to digitally recording and archiving the signal values for later processing. SID observers submit stripcharts or computer plots to the SID coordinator for visual inspection at the end of each month.
Many observers analyze their own stripcharts and computer plots.
Analyzed results are submitted via e-mail to the SID Analyst for correlation with other observers' results. The final SID report combines individual observers' reports with the SID Coordinator visual analysis. SID monitoring equipment can be constructed in a few hours by anyone with minimal electronics background. Components are easily sourced and many SID program participants are available to answer construction and operating questions. Only a few SID monitoring stations are presently located outside the United States.