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[AMPS] a sticky issue.

To: <amps@contesting.com>
Subject: [AMPS] a sticky issue.
From: 2@vc.net (measures)
Date: Sat, 14 Oct 2000 12:18:30 -0700
>Rich,
>
>Seems that issue is not that effective resistivity of nichrome increases 
>with decreasing frequency - I don't think anybody is arguing that. 


Mr. Rauch has.  He has also argued that most of current flows in the 
resistor instead of the inductor.  In the 28-November sample problem he 
proposed, slightly more than half of the current flowed through the 
inductor


>What is evident is that the effective series resistance of the nichrome 
>suppressor  is higher than conventional suppressor at low frequencies. From 
what I 
>can see, this seems to be the basic tradeoff  between the nichrome 
>suppressors
>and the conventional suppressors. If I am recalling the test data correctly, 
>the nichrome suppressor has higher losses at moderate VHF frequencies 
>(50 to 100 MHz) - a good thing, at the expense of higher losses in the HF 
>frequency range (a bad thing). 

So far, no one has reported seeing a drop in HF power.  Presumably, a 1% 
change on 10m barely shows up on the average meter.  In my opinion, the 
HF loss issue is a red herring.  

end

> As the frequency increases further the 
>the two suppressors start to converge as the inductive reactance of the 
>nichrome suppressor starts to dominate over the resistance of the wire.
>No rocket science here. 
>
>Mike, W4EF...................................
> 
>
>----- Original Message ----- 
>From: "measures" <2@vc.net>
>To: "AMPS" <amps@contesting.com>
>Sent: Saturday, October 14, 2000 12:14 AM
>Subject: Re: [AMPS] a sticky issue. 
>
>
>> 
>> >At 08:01 PM 10/13/00 -0700, you wrote:
>> >>
>> >>According to Wes, the copper-wire suppressor had an Rp of 166-ohms at 
>> >>100MHz and the resistance-wire suppressor had an Rp of 101-ohms.  More Rp 
>> >>means more gain.  Are you arguing the opposite, Bill?    
>> >
>> >Rich- I am NOT arguing either way, which may surprise you-  You are missing
>> >the point- your problem is that you misstate other peoples arguments-
>> >exaggerate their position, and make ALL debate into a personal attack.
>> >Your reference to others as "lapdogs" is a case in point- THat was uncalled
>> >for, 
>> 
>> During the grate debate, Tom's faithful lapdogs attacked my 1/1994 QST 
>> article, The Nearly Perfect Amplifier and stated that a rheostat simply 
>> will not work for adjusting filament potential (sic).  
>> 
>> >and made several people upset. some of the ones most upset were people
>> >who dont like Tom , either.
>> >
>> >>
>> >>Do you believe that the RF resistance of nichome wire increases as 
>> >>frequency decreases?
>> >
>> >Rich- I KNOW that the resistance of Nichrome wire changes with frequency.
>> 
>> ok 
>> 
>> >What I don't know is just where (what frequency range) , and how much it
>> >changes. I only know that at very low frequencies, it is higher that it is
>> >at very high frequencies.  
>> 
>> The resistance of all conductors increases as frequency increases.  As 
>> frequency increases, skin depth decreases, and conductivity decreases.  
>> This is why 10m tank inductors need more copper than 80m tank inductors.  
>> //  In Wes' measurements, the resistance of the nichrome inductor - with 
>> no parallel resistor - changes from 15-ohms at 10 MHz to 45-ohms at 
>> 200MHz.  Rauch's assertion that nichrome is different than all other 
>> conductors is a laugher.  
>> 
>> >Again- this has NOTHING to do with the problem. You keep interjecting this
>> >into posts on other subjects as if it was a sever indictment and a MAJOR
>> >error. 
>> 
>> It undoubtedly is.      
>> 
>> > You have taken this out of context, with mystifying results to all
>> >newcomers, 
>> 
>> How do you know what all newcomers think?
>> 
>> cheers, Bill.  
>> 
>> -  Rich..., 805.386.3734, www.vcnet.com/measures.  
>> end
>> 
>> 
>> --
>> FAQ on WWW:               http://www.contesting.com/FAQ/amps
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>> Problems:                 owner-amps@contesting.com
>> 
>> 
>
>


-  Rich..., 805.386.3734, www.vcnet.com/measures.  
end


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