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From: myers@hpfcdj.HP.COM (Bob Myers)
Newsgroups: sci.electronics
Subject: Re: Resistor types
Message-ID: <17660044@hpfcdj.HP.COM>
Date: 16 Jan 90 19:33:59 GMT
References: <1990Jan12.231715.28296@phri.nyu.edu>
Organization: Hewlett Packard -- Fort Collins, CO
Lines: 21

>>Film type resistors generally have the resistive material deposited
>>on an insulating rod, and then cut in a helical pattern using either
>>screw machinery or a laser.  These, and wirewounds, both are quite
>>inductive.  If low inductance is essential, composition types are
>>preferable.

>Non-inductive film resistors are available. I believe that a zig-zag pattern 
>is prepared on a plastic film then attached to a body for support and heat
>sink. I believe that they are only available in larger power sizes, which
>is where wire wound is mostly used.

It's also possible to get a low-inductance wirewound; ask if your resistor
manufacturer produces any with a "bifilar" winding, which is simply a
wirewound with the wire turned around and wound back over itself (or next to
the original turns) in the opposite direction, such that the fields cancel
(equal and opposite currents).


Bob Myers  KC0EW   HP Graphics Tech. Div.|  Opinions expressed here are not
                   Ft. Collins, Colorado |  those of my employer or any other
myers%hpfcla@hplabs.hp.com               |  sentient life-form on this planet.