After exiting I-29 at exit 18, going west (or north-?) into Platte City, MO, the speed limit changes from 55 to 45 to 35 m.p.h. within about 150-200 yds. from I-29. I was driving to a meeting at about 5 a.m., came off the I-29 north at exit 18, turned left onto state hwy 92 west toward Platte City, when I noticed that I was going a bit fast (about 55 m.p.h.) as I crossed over the interstate, and I knew that the speed limit would drop to 35 m.p.h. on just the other side of the first light on the edge of town. I watched my speed drop from 55 to 45, then as I crossed the first intersection at a green light, my speed was falling below 35 m.p.h. as I passed the 35 m.p.h. sign located just past the light. At about the same time, I noticed out of the corner of my eye that there was a Platte City policeman parked on the side of the road just past the 35 m.p.h. sign, and I thought to myself "Whew, I dropped to 35 just in time!". Sure enough his lights come on. I immediately pulled over, thinking "he must have got me for doing 55 in the 45." He came up to my car and said that he got me doing 55 in the 35! I know that this isn’t true as I was deliberately slowing down, and I know that I was doing no more than 35 when I passed the sign! Plus I am very careful about obeying posted speed limits. While my inattention should have cost me for the 55 in the 45, which was true, he cited me for the wrong speed. Intentional or not? I don’t know, but my opinion is that I was ripped off for about 10 m.p.h. on my ticket. You can draw your own conclusion, but mine was that I needed to buy a radar detector so I wouldn’t be caught in any dishonest speed traps ever again. I immediately ordered a radar detector, my first one. I never thought I would need it, and I don’t use it to speed even now, just for warning of what’s ahead of me.