I only found out about these a few months ago because there was always a cop leaning against one outside a ballpark before and after games with a radio plugged

I only found out about these a few months ago because there was always a cop leaning against one outside a ballpark before and after games with a radio plugged into it. I asked what he was doing and he gladly showed me that he was just manually cycling the lights, basically on a longer delay where required to clear jams and work with another cop directing traffic.