[ARC5] SI Units - Careless Errors Abound

[Mike Morrow]

> In Germany it was kHz and MHz ever since it was adopted.

Which was in 1930.

Other examples of careless unit errors are using:

  hz vs. Hz        Unit *symbols* are capitalized when it represents a proper name.

  Hertz vs. hertz  Units are NOT capitalized when spelled out (in English usage). 

  mHz vs. MHz      m in the SI system is 1/1000.
                   M in the SI system is 1000000.
                   mHz means millihertz.
                   MHz means megahertz.
                   (Using the wrong letter results in specifying
                    a value incorrect by a factor of 1000000000!!!)

  KHz vs. kHz      K in the SI system is Kelvin.
                   k in the SI system is 1000.
                   KHz means kelvin hertz (nonsense).
                   kHz means kilohertz.

  KV vs. kV        kelvin volts (nonsense) vs. kilovolts

So...it's best to drop incorrect mhz or mHz or Mhz for the correct MHz,
 and it's best to drop incorrect KHz or Khz or khz for the correct kHz.

Another common error occurs when units are combined, such as battery capacity:

A milliampere hour should be mA h, not mah or ma-h or mAhr or MAH or some
other combo.

Symbols should mean something.

Mike / KK5F