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Subject: Re: More Yellow Box Cap Questions

From: The Old Crow <oldcrow@...
Date: 1999-11-09

On Tue, 9 Nov 1999, Tkacs, Ken wrote:

> Are box caps marked "∗470 nk 63" and "D474 J∗" both 0.47mfd caps?

Yes. 470n = 470 x 10^-9 = 0.470 x 10^-6

474 = 47 x 10^4 x 10^-12 = 47 x 10^-8 = 0.470 x 10^-6

> And a rhetorical question--why is "violet" specified in the resistor
> color code when they always use lavender to mark the parts?

Resistor part colors tend to vary for specific colors. Sometimes I
think the factory personnel who program the marking machines try to play
mind games and create colors that are amazingly difficult to discern, such
as reddish-brown.

As far as the color scale goes, it they were orignally taken from the
"pure" color scale of chromatic light frequencies: red, orange, yellow,
green, blue, indigo, violet. The common mnemonic taught every astronomer
is "Roy G. Biv". Now, true violet might be tough to tell from black,
brown or blue on a resistor, thus they lighten it up a bit. Personally I
think they can afford to print the actual value on resistors anymore; they
got rid of capacitor color codes eons ago.

--Crow

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