LF: LF coil winding

[DK7FC <selberdenken@posteo.de>]

Hi Gary,

Thanks for the ideas and links. Of course i thought about double layer 
winding when designing the coil on the beginning... I think i cannot 
afford windings beeing so close together because of the high voltages. 
You can't imagine... ;-) 10 kV is nothing!
I want to try to use some test-tubes as a spacer and just a few double 
layer windings on the top of the coil. With 2 cm of distance, it coul 
work well i think. First i will remove 3 or 4 turns of the burnt litz 
wire. Then i want to try to get the same L with the shorter wire using 
that technique which has a better coupling and improved l/d ratio...
73, Stefan



Am 13.09.2015 20:11, schrieb Gary - G4WGT:
> Hi Stefan,
>
> Try pyramid winding, I am using this on my 136 kHz coil, saves space.
> A bit tricky to do though :-
>
> http://www.oz8nj.dk/spoler.htm
>
> And my coil :-
> http://myweb.tiscali.co.uk/wgtaylor/LF%20&%20MF%20Experiments%2010.html
>
> 73, Gary - G4WGT.
>
>
> -----Original Message----- From: DK7FC Sent: Sunday, September 13, 
> 2015 5:04 PM To: rsgb_lf_group@blacksheep.org Subject: Re: LF: R7NT 
> WSPR15
> Hi Jay,
>
> I think the guard ring above the upper winding of the coil lost its 
> contact to this winding. So it was floating. Or, the contact was loose 
> so there was a small arc that started to burn that ring down so the 
> structure became more and more inhomogenious, from a E-field view. 
> Well, at least it worked very well since 2011!
> I want to get even better results after the maintenance. There is some 
> room for improvements: The diameter / length ratio has never been 
> optimal on that coil. I want to check if it's possible to build a 
> double layer coil, at least a few of the upper windings... Effort but 
> interesting :-)
> 73, Stefan
>
> Am 13.09.2015 15:35, schrieb jrusgrove@comcast.net:
> > Stefan
> >
> > Any idea what started the meltdown?
> >
> > Heard someone say once: There are two types of LF ops ... those that 
> > have experienced fires ... and those that will ;~) .
> > Jay W1VD  WD2XNS  WE2XGR/2
> >
> >
> > ----- Original Message ----- From: "DK7FC" <selberdenken@posteo.de>
> > To: <rsgb_lf_group@blacksheep.org>
> > Sent: Sunday, September 13, 2015 9:16 AM
> > Subject: Re: LF: R7NT WSPR15
> >
> >
> > > Hi LF,
> > >
> > > Unfortunately my LF coil got damaged during transmitting a few weeks 
> > > ago. I'm soon repairing the coil and hope to join the 2200m band 
> > > then again.
> > > https://dl.dropboxusercontent.com/u/19882028/LF/20150910_193005.jpg
> > > https://dl.dropboxusercontent.com/u/19882028/LF/20150910_192916.jpg
> > > https://dl.dropboxusercontent.com/u/19882028/LF/20150902_182551.jpg
> > >
> > > 73, Stefan
> > >
> > > Am 13.09.2015 15:02, schrieb Mike Dennison:
> > > > Alex was also a good signal with me when he sent Opera 32 last night.
> > > >
> > > > Mike, G3XDV
> > > > ==========
> > > >
> > > >
> > > > > Hi Alex,
> > > > >
> > > > >
> > > > >
> > > > > sorry my WSPR is on strike, no uploads.
> > > > >
> > > > > Made it now manually.
> > > > >
> > > > >
> > > > >
> > > > > 1745 -35 1.1 0.137603 0 R7NT KN97 53
> > > > >
> > > > > 1800 -32 1.1 0.137603 0 R7NT KN97 53
> > > > >
> > > > > 1815 -35 -0.2 0.137604 0 UT7GH KN66 20
> > > > >
> > > > > 1845 -36 1.5 0.137603 0 R7NT KN97 53
> > > > >
> > > > > 1900 -34 1.5 0.137603 0 R7NT KN97 53
> > > > >
> > > > >
> > > > >
> > > > > 73 Joe
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > -----
> > > > > No virus found in this message.
> > > > > Checked by AVG - www.avg.com
> > > > > Version: 2015.0.6125 / Virus Database: 4419/10626 - Release Date:
> > > > > 09/12/15