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$f = \frac{1}{ 2 \pi \sqrt{ L(C_{\text{EXT} } + C_{\text{INT} }}}$

$F = G \frac{m_1 m_2}{r^2}, $

Fractur html entity names accepted: &Afr; &afr; &Bfr; &bfr; &Cfr; &cfr; Fractur unicode numbers accepted: &#x1d56c; &#X1D56C;

ℳ

αβΓγΔδΕεζηΘθΚκΛλΜμΝνΞξΠπΡρΣσςτυΦφΧχΩω

Mu &Mu; &mu;

Micro &micro;

Xi Χ χ

Psi Ψ ψ &Psi; &psi;

Chi Ψ ψ &Chi; &chi;

Wikipedia auto-conversion tests:

An inch is 1000 thou

SOT-223 pin pitch is 2.3 mm

SOT-223 pin pitch is 91 thou exactly.

Vacuum tube sockets have 8 pins on a inch circle.

TO-3 has two pins at exactly 0.430 inches apart. Assuming they a two of eight pins on a circle. This is roughly where they would be as two of eight pins on a inch circle. 0.43 / sin(45&deg;) = 0.608111832 = 9.729789309/16ths of an inch. Approximately 608 thou or inch.

Alternatively, a = 0.625 inch circle would produce pins 0.441941738 inch apart (1% too big). A = 0.6875 inch circle would produce pins 0.486135912 inch apart (13% too big). A = 0.6 inch circle would produce pins 0.424264069 inch apart (1.3% too small).

The 4-pin version of the TO-3 shows the pins are on a circle split into 5 segments, with a 5th pin absent. 0.215 * tan(18) = 0.069857735 which is very near the specified 0.0715 offset.

In fact, the relation of the pins to the centrum indicates

Most JEDEC packages are obsolete. Packages seen in current catalogues: