Message-ID: <20071228213441.zaaf02469gasokoo@webmail3.kuleuven.be>
Date: Fri, 28 Dec 2007 21:34:41 +0100
From: Rik Strobbe <Rik.Strobbe@fys.kuleuven.be>
To: rsgb_lf_group@blacksheep.org
References: 	<4774BB92.1080302@online.fr><000801c8496b$71b5b040$0e00000a@AGB>
	<20071228184913.wulh5g2r8z4sg4gk@webmail3.kuleuven.be>
	<001801c84981$dc57a780$0e00000a@AGB>
In-Reply-To: <001801c84981$dc57a780$0e00000a@AGB>
MIME-Version: 1.0
Content-Disposition: inline
User-Agent: Internet Messaging Program (IMP) H3 (4.1.2)
Subject: Re: LF: -HELP-  MMANA-GAL   Antenna analyzer .... can anyone'code'
	an array ?
Content-Type: text/plain;
	charset=ISO-8859-1;
	DelSp="Yes";
	format="flowed"
Content-Transfer-Encoding: quoted-printable
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org


Hello Graham,

the load (=3D loading coil) is at a rather unusual place: at the top of =20
the vertical wire. Or to be exact, one segment below the top.
If you want the load just above the feeding point just change "w1e1" =20
into "w1b1" (=3D one segment from the bottom).

The "trick" with MMANA is that wires only interconnect at their ends, =20
so the correct interconnection between a single vertical wire and =20
multiple horizontal wires is a bit tricky and need an number of short =20
wires.

Regarding earth: any wire at zero height is considered to be grounded. =20
So no need to worry about that.
As mentioned by G3YMC ground(loss) is not taken into account for the =20
impedance conculations. In my opinion this is a good thing, as this =20
allows to calculate the radiation resistance even al low efficiency.
At 136kHz and even at 500kHz it would be hard to calculate the losses =20
as greenery often plays a much larger role the soil. Beyond that the =20
waves penetrate that deep into the soil that only in very few cases =20
you can assume the ground is a uniform layer.

73, Rik  ON7YD

Quoting Graham <g8fzk@g8fzk.fsnet.co.uk>:

> Ok Thanks for that Rik,
>
> Thats the basic layout , ive only 2 top wires , but thats the layout ..
> I see you have a load defined in the geometry listing , but where on
> the ae is it located ? , I found one post on the user group , where a
> element could be given a short  lenght and have inductance added to  it
> .. that way you could control where the coil  was placed
>
> My ae has the 'coil' at the 90 deg bend , top of the vertical section ,
> if i could work out how to  add that, I  would be half way there ! the
> earth system would be the other half  hihi
>
> Tnx
>
> Graham ..
>
>
>
>
> ----- Original Message ----- From: "Rik Strobbe"  =20
> <Rik.Strobbe@fys.kuleuven.be>
> To: <rsgb_lf_group@blacksheep.org>
> Sent: Friday, December 28, 2007 5:49 PM
> Subject: Re: LF: -HELP- MMANA-GAL Antenna analyzer .... can
> anyone'code' an array ?
>
>
>> Graham,
>>
>> attached a MMANA-GAL file that simulates my 136kHz antenna when
>> adapted for 500kHz.
>> Maybe that will be of some help.
>>
>> 73, Rik  ON7YD
>>
>> Quoting Graham <g8fzk@g8fzk.fsnet.co.uk>:
>>
>>> -HELP- MMANA-GAL Antenna analyzer .... can anyone 'code' an array ?
>>>
>>>
>>>
>>> After several attempts .. and getting no-where  fast , Is there anyone
>>> who can code a top loaded antenna array ? the array is in the shape of
>>> a inverted L . with top  loading coil  and 2 wire capacity section
>>>
>>>
>>>
>>> I can find some similar files , but can I add to  them .... not as yet !
>>>
>>>
>>>
>>> It  'works'  up to  about  5 mhz , then falls over , I have a feeling
>>> the earth system is playing a part in this ... also how do  you code a
>>> parallel 2 wire section ?
>>>
>>>
>>>
>>> Any help would be appreciated ,
>>>
>>>
>>>
>>> Tnx
>>>
>>>
>>>
>>> Graham
>>>
>>>
>>>
>>> G0NBD
>>
>>
>>
>>
>> Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
>>
>>
>
>
> --------------------------------------------------------------------------=
------
>
>
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.516 / Virus Database: 269.17.9/1198 - Release Date:
> 12/26/2007 17:26



Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm