Visit radar bases in a single matchThis is probably one of the easiest challenges of the week, actually. You will have to visit five radar bases in the same game, which is quite easy if you have a vehicle, less so if you are on foot. The little trick is to take a UFO, since you will limit the distance between each point. Just know that we can find one on the island to the south, at the cod camp. Normally, not many players use it, but it's likely to be very popular this time around. You will have to hurry.
Once in the UFO (or a car), you will be able to follow a path to visit five radar bases in no time. If you ever don't know where to find them, know that one is present south of Misty Meadows, one in Slurpy Swamp, another east of Weeping Woods, another east of Dirty Dock and the last one at north of the map. You can find their location with more precision on the map below.
Finally, be aware that you are not normally required to get out of the vehicle to visit radar bases. You just have to get close enough to it for it to be compatibilized.