Hi,
I just would like to hear from fellow members what GPS they use to record their speeds and if they were able to measure it against something , a tachymeter for instance, how accurate it was. Id also like to know what datalogging you are using and hows that working out. I'm not interested in any debates or "they are not the holy grail stuff" who doesn't know that I just want your experiences to figure out what will be the best unit to buy. I know it may not be accurate to the trap but I need some semblance of measure other than rpm and pitch speed which is what I use to estimate speed currently. I do have plenty of chronographs with Tachymeters so I guess I could try to verify with that to see if I'm even in the right area at all with calculation.


Regards
Hubert

If you dont know what a tachymeter is:


A tachymeter (pronounced /t?ˈkɪmətər/) is a scale sometimes inscribed around the rim of an analog watch with a chronograph. It can be used to conveniently compute the frequency in hours of an event of a known second-defined period, such as speed (distance over hours) based on travel time (seconds over distance), or measure distance based on speed. The spacings between the marks on the tachymeter dial are therefore proportional to ​1⁄t, where t is the elapsed time.
The function performed by a tachymeter is independent of the unit of distance (e.g. statute miles, nautical miles, kilometres, metres etc.) as long as the same unit of length is used for all calculations. It can also be used to measure the frequency of any regular event in occurrences per hour, such as the units output by an industrial process. A tachymeter is simply a means of converting elapsed time (in seconds per unit) to rate (in units per hour)