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From: spt@peace.waikato.ac.nz (Simon Travaglia)
Newsgroups: sci.electronics
Subject: Re: Resistor types
Message-ID: <1990Jan19.024232.20035@peace.waikato.ac.nz>
Date: 19 Jan 90 02:42:32 GMT
References: <1990Jan12.231715.28296@phri.nyu.edu> <1370@milton.acs.washington.edu>
Organization: University of Waikato, Hamilton, New Zealand
Lines: 29

In article <1370@milton.acs.washington.edu> whit@milton.acs.washington.edu (John Whitmore) writes:
>In article <1990Jan12.231715.28296@phri.nyu.edu> roy@phri.nyu.edu (Roy Smith) writes:
>>
>>	What are the significant differences between the various resistor
>>technologies for "typical" resistors, say 1/4, 1/2, or 1W in 1-ohm through 10
>>Megohm values?  Looking through the Newark or Mouser catalogs, you can find
>>carbon film, carbon composition, metal film, and metal oxide, not to mention
>>wierdo stuff like silocone coated, vitreous enamel, and wire wound.
>
>  Wirewound resistors are expensive for high resistance
>values, mainly used in the 0.1 ohm to 10,000 ohm range.

The only negative aspect of wirewounds is that they are rather bulky
(but then you should expect that if you have an application that requires
them)

>	Carbon is a semiconductor; at low temperatures (liquid nitrogen)
>a carbon resistor makes a GREAT sensor; when the resistor hits the nitrogen,

I used to have a mate who Loved carbon resistors because you can "tune" them
by filing them with a small file.  (He used to play with cheap&nasty music
circuits, and used a file to tune up the carbon resistors (3c .vs. about 20
for a trim pot)  I don't know how this would effect the "hot spot" problem
tho, it may create one.
-- 
SimonT, spt@grace.waikato.ac.nz, Univ of Waikato, Private Bag, Hamilton NZ.
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