>
>Rich,
>
>Is Wes' raw impedance data for the conventional and
>nichrome suppressors published anywhere?
? on Wes' Web site, perhaps. There is a graph on my Web site that shows
the differences in Q at 100MHz.
>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.
>
agreed, Mike. Conclusions often carry an agenda.
If you can't find a complete data page, I could try to make a PDF file.
Cheers
, 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.
>> >>
end
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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