Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!elroy.jpl.nasa.gov!lll-winken!aunro!aupair.cs.athabascau.ca!rwa From: rwa@cs.athabascau.ca (Ross Alexander) Newsgroups: sci.electronics Subject: Re: Gold saves energy. Message-ID: Date: 6 Jun 91 18:02:21 GMT References: <1991Jun5.163512.1314@zoo.toronto.edu> <44194@netnews.upenn.edu> Organization: Athabasca University Lines: 24 touch@gradient.cis.upenn.edu (Joseph D. Touch) writes: >In article <1991Jun5.163512.1314@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes: >>To improve the conductivity of the cables, you're going to have to replace >>the bulk material, not just add a plated surface. >Are you sure? I thought AC travelled on the surface of the wire, not >in the bulk, or is this just a very high frequency phenomenon? Skin effect is a function of frequency. At DC, it's nil. It doesn't get particularly important until you're up around 100 MHz. Qualification of last statement: yes, I know all the lofer phreaks wind their stuff from Litz wire and they're only at 160 KHz or so. But I'm speaking of the really high-power domain, like kilowatts. At lower powers, does it really matter much that a % or two of the power is heating the cable? Not to me, for one. Also: a quick look in the Rubber Bible reveals that silver is significantly better than gold as a bulk conductor. Of course, silver is much more suspect to corrosion, but you can cure that with a coat of varnish. It's fairly common practise to silver-plate VHF and UHF cavities, but only the military bother to do this at HF. -- Ross Alexander rwa@cs.athabascau.ca (403) 675 6311 ve6pdq `You were s'posed to laugh!' -- Zippy