BTW did you know that FlightRadar24 and FlightAware don't show you all the aircraft you could be seeing?
For instance, you'll never see military aircraft, private jets from the uber wealthy, or even, say, the Sonoma County Sheriff's helicopter: https://www.flightaware.com/live/flight/N108SC
This is why things like Airplanes.Live are so valuable. They get data from a network of hobbyists with base stations (like me!), who share and publish open data for the joy of it.