• An AC/AC transformer reduces the voltage of the Power Line input to about 12VAC.
• 12VAC signal is input to an OpAmp configured as a high gain voltage comparator.
• The OpAmp generates a square wave output that it transmits to a Micro Controller digital input.
• The Micro Controller measures the number of 12MHz clock cycles between input leading edges of the power square wave.
• A PC client application to collects the frequency information from the Micro Controller by RS232.
• The client application connects with a web service and uploads the data periodically depending on local bandwidth.
• Each Data record in the upload contains Frequency, Server (NIST) Time, Authorization ID, and PIN. 
• The Power Frequency Monitor operator can access a Profile record on the web server.  The Profile record contains Location specific information including Local Frequency, Time Zone, Power Grid, Contact EMail address, and options to Download the data in XML format or clear the dataset.
• A Web Server Application displays live data from all connected Power Frequency Monitors and updates periodically depending on server bandwidth and client connectivity and displays the selected Power Frequencies on a live strip chart.

The current work in progress is Model 9.  Model 9 software and can be found in the downloads