>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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