Rich,
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.
Mike, W4EF...........................................
----- Original Message -----
From: "measures" <2@vc.net>
To: "John Simmons" <ka4u@vnet.net>; "AMPS" <amps@contesting.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
suppresser
> >resistors cooked and it seem to me the the combination of the resistance
and
> >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
my
> >> >bed time here on the eastcoast so it may be tomorrow before i can find
it.
> >> >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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