[HBR] about resistors

[Bill Cromwell]

On Sun, 2012-05-06 at 15:31 -0500, Chris Howard w0ep wrote:
> That was very helpful!
> 
> I didn't communicate very well, in that I was also
> (or mostly) interested in the wattage of the resistors.
> 
> If you have similar info for wattage,
> that would be really great!
> 
> 
> Chris


Hi,

Tim did a good job. You already know now how to use the current and
voltage to select a resistor. Use the current and voltage to determine
the rating in watts. Multiply the voltage by the current and that equals
watts. That cathode resistor will be dropping the about 8 volts (the
voltage you will measure if you put a voltmeter across the resistor) and
the cathode current - which is also the resistor current - was 9
milliamps in Tim's example. 8 X .009 = .072 watts. A one watt resistor
*should* be okay but I'm one of those guys who would put in a 2 watt
resistor if there is room for it. A quarter watt or half watt resistor
won't survive there for very long.

I hope that helps.

73,

Bill  KU8H