I always see this trap when travelling towards Sacramento from Reno. They are there probably 75% of the time. It is a combination of both radar and laser enforcement. A single copy hangs out by his car with the laser gun shooting at oncoming (westbound) traffic, while chase cars are stationed at the next overpass, on the on-ramp mostly out of sight. My best advice if you travel this area often is to slow to the speed limit (65 mph) at the Applegate exit and stay at that speed until you pass the Dry Creek Road exit. That should keep you safe.