On Sun, 10 Jul 2005 21:21:34 -0400, "KC4IH"
wrote:


I need to build a 3db pad, 50 ohm, 10 watt, to reduce the drive to my 6
meter amp. I need 2 X 300 ohms and 1 X 18 Ohm resistors and thought it would
be an easy matter to find them with enough current rating to do the job but
can't find anything larger than 1 watt carbon (not film, which are somewhat
inductive ) resistors. I can find want is called non-inductive wire wound
resistors. I can't understand how a wire wound resistor can be
non-inductive. Could someone explain this?

I found a graph that I copied off the web sometime back showing the
reactance of various R vs freq for metal film resistors. The 10-1000
ohm range of resistors show as being dead flat at 50 MHz compared to
DC...and well beyond. Above and below values tend to go nuts with
frequency, the high 100k values in particular.

I don't remember where I found this graph but based on it I'd think you
have a good chance of making those particular values work using garden
variety ten-cent 1-watt resistors...thinking along the lines that
manufacturing of plain old carbon film resistors would follow the same
trend.

I think its worth a try.

-Bill