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[AMPS] 2000 ARRL Handbook question

To: <amps@contesting.com>
Subject: [AMPS] 2000 ARRL Handbook question
From: 2@vc.net (measures)
Date: Tue, 1 Aug 2000 20:39:56 -0700
>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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