Warren - K2BM
At 06:39 AM 8/2/00 -0700, Michael Tope wrote:
>Is Wes' raw impedance data for the conventional and
>nichrome suppressors published anywhere? Without any
>data to study, this debate ends being more like a
>political battle than scientific inquiry. Seems like
>letting everyone see the impedance data for themselves
>would settle the matter.
>----- Original Message -----
>From: "measures" <email@example.com>
>To: "John Simmons" <firstname.lastname@example.org>; "AMPS" <email@example.com>
>Sent: Tuesday, August 01, 2000 8:39 PM
>Subject: Re: [AMPS] 2000 ARRL Handbook question
> > >Rich
> > >on page 13.26
> > >"Some designers use nichrome wire for L(sub)z but there is no credible
> > >evidence of any fundamental difference in performance as a result."
> > >The same statement is in the 99 Handbook.
> > ? John -- The same statement (by Ehrhorn) was in the '95 Handbook.
> > This was before Wes' tests with the Hewlett Packard Impedance Analyzer.
> > The test evidence showed that a resistance wire suppressor lowers VHF-Q
> > by a bit over 40%. This is probably a conservative number because we
> > currently use resistance wire that has about 70% more resistance than the
> > wire used in Wes' tests. However, if resistors were available that had
> > roughly 10nH of L, And would dissipate at least 30w, an even lower VHF-Q
> > suppressor could be built with copper wire. Cesiwid Co. told me they
> > could manufacture such resistors. The asking price for a min. order was
> > about 10 kilobucks.
> > >I don't know if that is what you were referring to but I have seen
> > >resistors cooked and it seem to me the the combination of the resistance
> > >inductance in the nichrome wire would be a better way to go IMHO.
> > ? True. Nichrome can safely operate at dull red heat. Carbon-comp.
> > resistors can not. The weak link has always been R-supp. The problem is
> > in finding a suitable resistor. Using resistance wire for L-supp helps a
> > bit. MOF resistors help a bit. -- Mr. Murphy was right. Everything
> > is more complicated than it looks. //. Congrats to Mr. G. W. Fyler.
> > Congrats to Mr. F. E. Handy.
> > cheers, John
> > >measures wrote:
> > >
> > >> >I will see if i can find it and get back to you. I t is getting near
> > >> >bed time here on the eastcoast so it may be tomorrow before i can find
> > >> >John
> > >> >
> > >> Thanks, John, however I already have the info.
> > >>
> > >> - Rich..., 805.386.3734, www.vcnet.com/measures.
> > >> end
> > >
> > >
> > - Rich..., 805.386.3734, www.vcnet.com/measures.
> > end
> > --
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