On a "dog bone" capacitor, orange = N150 (-150 ppm/degree C nominal
temco) and yellow = N220. These are handy for compensating for the small
temperature drift of a good toroidal VFO inductor wound on type 6
powdered iron, by using NPO for most of the tank capacitance, and N150
or N220 for the rest.

Roy Lewallen, W7EL

Paul Burridge wrote:
Hi,

If the black-tipped ceramics indicate NPO., what is signified by the
orange-tipped and yellow-tipped varieties?

p