From: "Malcolm Watts"
Date: Tue, 24 Oct 2000 19:08:51 +1300
Subject: Re: [TSSP] The Q answer!?
Hi Paul, > If your low Q is entirely due to sonotube loss and if this kind of > loss is typical of sonotubes then the advice should be to not use > sonotubes for CW coils - the performance is reduced from what it > should be by a factor 4 or more! > > I can see the 'Q chamber' is going to be busy for a while! > > Malcolm, what was the coil former used in your > Aug 96 Q measurements? The tri-file set of msmts with the disks was done on yellow HDPE gaspipe. The other set Dr Rszezotarski passed onto you (the mishmash set of coils) were wound on PVC and acrylic formers. I was so disgusted with the one coil I made on sonotube that I dumped it. When I first measured its Q I couldn't believe what I was seeing! I finally had to accept the evidence after exhaustive checks. Regards, Malcolm
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.