Speed feedback signs perform the same functions as radar trailers but are permanent. Real-time speeds are relayed to drivers and flash when speeds exceed the limit. Speed feedback signs are typically mounted on or near speed limit signs and can also be mobile units.
Advantages
- Real-time speed feedback
- Does not physically slow emergency vehicles or buses
- Permanent installation
Disadvantages
- May require power source
- Only effective for one direction of travel
- Long-term effectiveness uncertain