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From: durham@w2xo.PGH.PA.US (Jim Durham)
Newsgroups: sci.electronics
Subject: Re: Ridiculous Impedance
Message-ID: <128@w2xo.PGH.PA.US>
Date: 27 Aug 90 06:19:48 GMT
References: <1770009@otter.hpl.hp.com>
Reply-To: durham@w2xo.UUCP (Jim Durham)
Organization: Jim's Basement , Gibsonia, PA.
Lines: 23

In article <1770009@otter.hpl.hp.com> tgg@otter.hpl.hp.com (Tom Gardner) writes:
>Mini quiz:
>
>Most coax cables have a characteristic impedance of 50 ohms or 75 ohms.
>
>Why does TAT-7 (Trans-Atlantic Telephone cable number 7) have a characteristic
>impedance of 61.8 ohms?
>
>I'll give a piece of wedding cake to the first person with the correct 
>answer.


Well, I dunno about why, but 61.8 ohm cable would sure be handy. A 1/4
wave section of this would match 75 to 50 ohms very nicely for those
of use with lots of 75 ohm aluminum hard line available and 50 ohm
antennas. Where can we get some?

-Jim

-- 
Jim Durham
internet:  durham@w2xo.pgh.pa.us       ham packet radio:
	   jcd@cs.pitt.edu		w2xo@w2xo.#wpa.pa.usa.na