Ralph Mowery wrote:

I reparied an old VFO for a friend. In it was a 10 K 7 watt resistor.
It is about the size of a USB memory stick and looks likeit was dipped
in a mix of sand like the mortor used for bricks.

I saw an artical where someone else had the same problem with that
resistor.

Are they just wire wound or something special, like a fuse resistor ? I
have seen just a few of them, but never checked them out.

Your description sounds like an ordinary ceramic wirewound resistor. Be
sure to replace with a noninductive type. (Note that noninductive wirewounds
are still really very inductive.)

If you're worried about it, measure it. When these things fail, it's
usually by rising in value and not falling.

If it's bad, try mouser part number 71-CP10-K-10K.

If it's in a VFO, it might be used as a heating element to keep the
electronics in the can at constant temperature, in addition to its obvious
application in the schematic.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."