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>Från: measures <measures@vcnet.com>
>Till: "cd" <bearl@ozemail.com.au>, "AMPS" <amps@contesting.com>
>Ämne: Re: [AMPS] Nichrome/Parasitics/ARRL Handbook 2000
>Datum: mån 7 feb 2000 18.58
>
>
>>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
>
>
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>
>
>
>
>w4ETO
>
>>VK3HE
>>
>
>
>- Rich..., 805.386.3734, www.vcnet.com/measures.
>
>
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