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Re: Capacitor terminology



Naaah - in the REAL old days, capacitance was measured in 'jars'
and more recently microfarads could be abbreviated as uF
using the u to stand in for mu. (= 1E-6)
This sub-convention provided an alternative meaning for mF
which just possibly could stand for millifarads
- but not often...

....and anyone who knowingly uses mF to mean millifarad is just
being mean! My father made his first transmitting capacitors
using tinfoil and glass plates. By the time I got on the air
we could buy complete ARC-5 transmitters almost ready to go on
the ham bands for $5.00. Hook up a power supply and the world
was on your desktop (well, at 2 am, anyway).

(Sigh)

Leigh

A formula I memorized for my first amateur exam:

K A
C = 0.224 ----- (n-1)
d

This is the capacitance (in pF, which I now call "puffs") of
an n-plate capacitor, dielectric constant K, area of plates A,
and plate separation d. All dimensions are in inches, of course.

Sure wish I could reprogram those useless memory locations.