2K2?

[Magnus Danielson]

From: matti at devo.com
Subject: 2K2?
Date: Sat, 13 May 2000 18:53:09 -0500

> okay, now I'm feeling silly, but I have no idea what 2K2 means, in the context 
> of a resistor. (or 2M2, for that matter)
> 
> at http://www.uoguelph.ca/~antoon/gadgets/555ex6.gif, (no, I _do_ like the 555, 
> and I need the practice), the very upper left hand resistor says 2K2 for it's 
> value. What's this mean?

This is a shorthand notation in which the prefix has replaced the decimal
point. In effect this means that 2k2 is really 2.2 k which is intended to mean
2.2 kOhm. This system also has a unit prefix so that 220R means 220 Ohm and
4R7 means 4.7 Ohm where R is logically from Resistance, some great unit huh?

While this is a great missuse of the SI system it does carry some benefits.
For instance, if you would risk loosing the decimal dot in poor copying etc.
it comes out much clearer in this system. Another benefit is that it allows for
system in which only alfanumeric characters may be used to convey the correct
value.

It is in quite common use but is really a missuse like many other habbits.

Cheers,
Magnus