TECH: Are Ceramic Disc Capacitors polarized ?

[Guest]

Archived from groups: rec.games.pinball (More info?)

Here's one for the techies. I am re-doing a Bally CPU board & I have
some caps in the corrosion area that I want to replace. The ceramic
disc caps have a little sideways diamonds with one half of it filed in
black. My replacement caps have a number with an underline, NO longer
lead, NO stripe. How can one tell polarity if :

A: the lead is longer,

B: simple stripe on one leg,

C: NO marking, other than a number

Is there a standard for this kind of thing ? Do I have to look up the
data sheet ? Some catalog copy says, "polarity indicated" does that
mean POSITIVE or NEGATIVE ? Other types of caps are clearly marked, but
these tiny ceramic caps don't have much surface area. Is there some
king of "DaVinci Code" at work here?

I think I know the answer to some of these questions, but THINK I
KNOW , is the most DANGEROUS sort of knowledge.

Pinball Bob

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Ceramic caps for the most part are NOT polarized. There are a few
electrolytics in the reset section that ARE, but the discs are not.

Polarity indicated means that the marking will show which is pos and
neg.

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Bob,

Just to be clear, you are talking about caps and not the three diodes,
right? The caps are not polarized, so either direction is fine. As a
quick check, if a radial part (leads side by side like an LED) has a
polarity, the ground lead is the shorter wire.

K2