warning: KTY84

[Martin Czech]

I tryed the Philips KTY84 this weekend.  Mmmh, why does it have this
ring marker?  My ohm meter says, that it has different resistances
depending on polarity. Oooops!! Another look into the data sheet shows
a box where it says : ring to negative!

I should have known this. These things are clever linearised thermistors,
linear in one quadrant.

Our vcos should be designed so that an input voltage of 0V gives a medium
frequency, thus minimising the error. That means bipolar input voltages
are used, you can't  use KTY84 type devices for that. But other circuits
may have only one polarity, there these thermistors could be used.

I'll have a further look at it as soon as my temperature test chamber
is ready.  I've finished the mechanical construction part now, this is
the part I sure hate the most.

m.c.