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[AMPS] Nichrome/Parasitics/ARRL Handbook 2000

To: <amps@contesting.com>
Subject: [AMPS] Nichrome/Parasitics/ARRL Handbook 2000
From: measures@vcnet.com (measures)
Date: Mon, 7 Feb 2000 11:58:28 -0700
>Those of you that have not picked up, or had a look at the new ARRL 
>Handbook 2000, there is some mention now of Nichrome Parasitic 
>suppressors. It reads as follows in chapter 13.26.
>
>"Some designers use nichrome or other resistance wire for L2, but there is 
>no credible evidence of any fundamental difference in importance as a 
>result." It goes on to say that W4ETO, amplifier manufacturer has never 
>seen an HF amplifier using modern tubes that could not be made completely 
>free of VHF parasitics by using one of the simple parasitic suppressor 
>contruction described above" It does not mention what "advanced" 
>techniques should be used!
>
>Anyway for those curious have a read.
>
Craig --  This was written by Dick Erhorn / W4ETO for the 1995 Handbook, 
several years before N7WS/Wes' measurements of copper-wire vs 
resistance-wire suppressors.  .  My guess is that Dick never read G. W. 
Fyler's article on parasitic oscillation in the Institute of Radio 
Engineers' Journal.  //  Sure, the decrease in VHF Q is only about 41% 
with resistance-wire VHF parasitic suppressors, however, this might be 
enough to make a difference.  

cheers







w4ETO 

>VK3HE
>


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


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