I work in sales and travel in PA a lot.
Ive heard they use ENRADD.
I never heard of this until using this website. I read about it and it seems like a pretty foolproof way to measure speed.
However, I still see some ways to detect it.
1. visual sighting of the ENRADD devices. If I know what to look for, I may be able to see the reflective device on the side of the road - if its daytime.
2. scanner. It says there is a wireless link. If I knew what frequenc(ies) it transmits on, I could hear a 'blip, or blirp' of electronic data transmitting on that frequency. This would in turn alert me to its presence ahead.
What are your thoughts on this technology and how to detect it?