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Poor Form? (fwd)
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From: Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent: Sunday, February 15, 1998 4:10 PM
To: Tesla List
Subject: Re: Poor Form? (fwd)
Hi Gregory,
> Date: Thu, 12 Feb 1998 11:07:30 +0000
> From: "Gregory R. Hunter" <ghunter-at-mail.enterprise-dot-net>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Poor Form?
>
> Dear Folks,
>
> Thanks for answering my query about sonotube. I've seen it before
> at construction sites, I just didn't know it was called "sonotube".
>
> One writer has suggested that this may be a poor choice of coil
> form. Is cardboard tube lossy or something? For low RF losses, I
> would think well-sealed cardboard would be nearly as good as air, and
> superior to PVC.
>
> Greg
>
> Dreaming of Megavolts in East Anglia, UK
Some people have used Sonotube with excellent results. The key is the
preparation ( **complete** drying and sealing with good quality
laquer/varnish).
A couple of years back I was going to build my all-time best
coil on a piece of Sonotube rescued from a rubbish skip. I didn't
prepare it all well and got the result I deserved - an unloaded Q of
around 60 and that was with a space wind to boot. Sonotube can be
great but you have to do a thorough job on it.
Malcolm