Content-Transfer-Encoding: 8bit
Message-ID: <DDC408CAE72CD511827A0002A5131CD6D9F5E8@exc_wil08>
From: "Ashlock,William" <William.Ashlock@edwards.boc.com>
To: rsgb_lf_group@blacksheep.org
Subject: LF: RE: Re: RE: Re: Re: [Lowfer] RE: litz wire
Date: Tue, 21 May 2002 23:11:05 -0400
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1; format=flowed
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Sender: <majordom@post.thorcom.com>

Mal,

As the result of becoming gray from learning how to do things the hard way,
I now conclude that it is far better to FIRST lay out the theory of what I
am intending to design. This would include a sufficient number of equations
describing the behavior of all the variables. Then I do the best job I can
to verify the math using bench tests of all components. As a final step I
determine if the performance of the design is as predicted from the math. If
not, I go back to the design equations and determine what went wrong and
then begin the process over again. Note, that for LF antenna designs where
nothing is a certainty, my approach is NOT to simply set up a the new
antenna and call up my friend 40 miles away and ask for an S reading. 

In terms of the use of #12 Litz wire (the subject of miles of postings over
the last two weeks), I have just designed a 4X #12 cable for my 50'/50' loop
using the above approach that has an AC resistance including ground loss of
0.39 ohms. As far as I know this is the lowest resistance ever achieved for
a TX loop antenna of this size at 185k. And yes, anyone doubting this
measurement, may stop in and check it out.

Thank you for the help in the soldering problem my friend but I do not wish
to continue a dialog of 70% unmeasured, and unverified BS.

Regards
Bill 
   
-----Original Message-----
From: hamilton mal [mailto:g3kev.ham@virgin.net]
Sent: Monday, May 20, 2002 1:14 PM
To: rsgb_lf_group@blacksheep.org
Subject: LF: Re: RE: Re: Re: [Lowfer] RE: litz wire


----- Original Message -----
From: "Ashlock,William" <William.Ashlock@edwards.boc.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Friday, May 17, 2002 8:39 PM
Subject: LF: RE: Re: Re: [Lowfer] RE: litz wire


> Mal,
>
> >I have wound a loading coil using decca 729 strands litz and another
2.5mm
> >teflon insulated wire one and compared results. On air measurements and
> >reports are identical, regardless of what theory dictates.
>
> Am I going to have to send you a loading coil made from #12 copper and and

Bill. Try HW #12 pure copper tube, not the alloy mix you get these days for
commercial wiring and plumbing, even better SPT (silver plated tube tube)
Gold plate tube even better, very low RAC. These are all easy to solder and
although hard to get out perform all other varieties, available in all sizes
from diameters barely visible to sizes that need a fork lift to move about.
73 de G3KEV


> another with identical dimentions from #12 Litz to prove to you there is a
> 2x reduction in Rac? Assume you have a way to make these measurements?
Using
> on-air measurements as a way to measure a change less than 3db is not a
> sound approach, especially if the A/B change can't be accomplished by
simply
> flipping a switch. This change in fact could be under 2db due to the
> additional series resistance in the circuit added by soil loss.
>
> Regards,
> Bill A
>
> _____________________________________________________________________
> This message has been checked for all known viruses by UUNET delivered
> through the MessageLabs Virus Control Centre. For further information
visit
> http://www.uk.uu.net/products/security/virus/
>
>


_____________________________________________________________________
This message has been checked for all known viruses by UUNET delivered 
through the MessageLabs Virus Control Centre. For further information visit
http://www.uk.uu.net/products/security/virus/

_____________________________________________________________________
This message has been checked for all known viruses by UUNET delivered 
through the MessageLabs Virus Control Centre. For further information visit
http://www.uk.uu.net/products/security/virus/