[aprssig] grads and other funny angle measurements

Matti Aarnio oh2mqk at sral.fi
Wed Apr 15 13:40:53 EDT 2009

On Wed, Apr 15, 2009 at 08:35:17AM -0700, Steve Noskowicz wrote:
> >...> When working with a theodolite I usually use grads.
>    Ahhhh!  So THAT'S where grads are used !

Yup.   90 degrees = 100.00000000 grads


Theodolites I have used could output data in multiple forms, but
bootup default was grads with decimals:  -ggg.ggggggggggggg

There are some very esoteric math reasons to prefer that form
when doing geodetic calculations with pen and paper.  With modern
computers that little help is not particularly necessary, as
everything gets converted to radians for calculations.

> -- 73, Steve, K9DCI

73 de Matti, OH2MQK

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