resistors,Bc168 replacement

[Magnus Danielson]

From: "Hans-H.Klos" <xmurz at gmx.de>
Subject: resistors,Bc168 replacement
Date: Fri, 17 Nov 2000 16:12:26 +0100

> Hello!

Hi there!

> Some stupid question I have to ask:
> what is the difference between a 1/4w and a 1/8watt resistor.
> In what way does it react differently. I'm new to all this, so please
> give me some advice. 

The 1/4 W resistor is supposed to withstand 0.25 Watt of heat
disipation without seriously considering giving up the gost. The 1/8 W
resistor is not designed for 0.25 Watt but rather for 0.125
Watt. Thus, you have to select the wattage of your resistors such that
they will not blow or smoke up on you as you run your curcuit in
normal operation. The simple rule of thumb is

          2
         U       2
P = UI = -  = R*I
         R

P may thus never go beyond the marking (well, for static power, peak
power may go bejond, but you should be very carefull).

Cheers,
Magnus