Coming This Summer: Speed Limit

[Dave R]

Originally Posted by Silver Duck

Actually, it would be fairly straight forward to calibrate the Raymarines:
1. Turn a few handheld GPSs into "transfer standards" by comparing their readings (on land) to radar guns which have been shown to be accurate and whose readings are acceptable in court.
2. Put those GPSs aboard boats and make repetitive test runs past the Raymarines at a range of speeds, while documenting both the GPS readings and the Raymarine readings. (I'd do this using multiple GPS-carrying boats travelling in multiple directions concurrrently.)
3. If the GPS readings agree with the Raymarine readings, you've calibrated the Raymarines and the data they produce should be acceptable in court.

Silver Duck

You know and I know this would work fine and make reasonably accurate measurements, but a lawyer would have a field day with this method. This method basically has a radar set calibrated by a GPS device which is calibrated by a hand held radar unit which is calibrated by a standard in some lab. Too many links in that chain and too many opportunities for error to prosecute someone unless they were grossly over the speed limit, in which case testimony alone would probably suffice.

[GWC...]

Originally Posted by Dave R

Well, if someone were to challenge a ticket, they'd have to ask how the radar is calibrated etc. That would end that coiurt session in a hurry.

Next time on the Lake, why not visit one of the MPs doing the speed checks and ask how they are calibrated...

http://www.citizen.com/apps/pbcs.dll...321/-1/CITIZEN