Hi,

Jetpilot, the translator is just funny ;-)

very nice antennas --> antennas quite pleasant

who are the two beautiful woman? --> what is the woman two beautiful?

thanks for the post --> thanks to the connector

We have to use very simple (linear) phrasing ;-)

(what about reverting the translation back to original?)

***Congratulations for the nice works presented by Sarmento***

Have all a nice season there ;-)

Jose' Silva / CT1AXG / Portugal


--- In loopantennas@yahoogroups.com, "gmcjetpilot" <gmcjetpilot@...> wrote:
>
> Great work. Very nice antennas. However what is even better, who are the two
beautiful woman?
>
> GRANDE TRABALHO. antenas muito agradáveis. entretanto que é mesmo melhor, que
é a mulher dois bonita?
>
>
> Sorry I can't help with the Litz wire question, but thanks for the post. I
read about the power outage in Brazil.
>
> I pesaroso can' ajuda de t com a pergunta do fio de Litz, mas agradecimentos
para o borne. Eu li sobre o falho eléctrico em Brasil.
>
> Bom por meu amigo
>
> (PS - I don't know Portuguese, just the translator on the computer. I have
been to the Azores many times, which is part of Portugal.)
>
>
>
>
> --- In loopantennas@yahoogroups.com, "sarmento2k" <sarmento.campos@> wrote:
> >
> > Hi
> >
> > This is my first post on this group, and I would like to show some pictures
of two loop antennas I like most, mainly for MW dxing.
> >
> > The first one, a square loop made with wood, which is either coupled
passive, to portable receivers like Sony ICF-2001 or active, with a preamp
buffering low impedance matching to 50 Ohms input of Icom R75.
> >
> > http://www.sarmento.eng.br/LoopQuadroOM.htm
> >
> > (it´s in Portuguese, but you may also see the calculations used on it)
> >
> > The other one, is a loop stick ferrite antenna.
> >
> > http://www.sarmento.eng.br/LoopFerriteRGP3.htm
> >
> > Recently, I have found in my messy shack :-) some Litz wire, and I did a new
coil based on it, and performance on MW is really a must comparing to the
magnetic wire 23 AWG.
> >
> > The Litz wire used is composed by 60 strands of 40 AWG, in theory, not the
right one to MW, but it looks fine comparing to enameled wire 23 AWG.
> >
> > Just to point that the day of the recently shaming blackout in Brazil, I
listened to BSKSA Jedah, Saudi Arabia, 1512 kHz with excellent sound, using this
antenna and a Sangean ATS909.
> >
> > Post at :
http://blog.sarmento.eng.br/2009/11/11/blackout-no-brasil-oportunidade-impar-par\
a-a-radioescuta/
> >
> > My question,is about Litz wire, does anyone have tested and compared the
same kind of loop using different wires to measure its gain over "regular" one ?
> >
> > Best Regards
> >
> > Sarmento Campos
> > Rio de Janeiro - Brazil
> >
>

Hi,

Considering the windinds process for air coil loop, I have being using enameled
copper wire.

I have seen lots of loop projects basically using standard stranded wire,
instead of the magnetic wire used mainly in transformers.

My initial post is about litz wire in ferrite loops, but both subjects are
interconnected.

I haven´t found yet a source proving in practical terms what´s the best material
to achieve higher performance on MW (abstracting Litz wire for RF).

Does anyone has observed any practical differences in such approaches ?

Thks
Sarmento - Rio de Janeiro - Brazil

The lower the resistance in the wire, the better.  Stranding vs. unstranded only
makes a difference if the resistance is lower.  Litz wire should be excellent. 
A loop made of monster speaker wire is probably better for the same size. 
Copper plumbing pipe - the 1/4 inch type, would probably be even better.  Low
resistance = high Q = good loop.  But bigger loops are always better, they can
eclipse the choice of wire.

Two types of discussion I always bow out of:  shielded and coax loops, and
un-tuned loops.




--- In loopantennas@yahoogroups.com, "sarmento2k" <sarmento.campos@...> wrote:
>
> Hi,
>
> Considering the windinds process for air coil loop, I have being using
enameled copper wire.
>
> I have seen lots of loop projects basically using standard stranded wire,
instead of the magnetic wire used mainly in transformers.
>
> My initial post is about litz wire in ferrite loops, but both subjects are
interconnected.
>
> I haven´t found yet a source proving in practical terms what´s the best
material to achieve higher performance on MW (abstracting Litz wire for RF).
>
> Does anyone has observed any practical differences in such approaches ?
>
> Thks
> Sarmento - Rio de Janeiro - Brazil
>

--- In loopantennas@yahoogroups.com, "rbrucecarter" <rbrucecarter@...> wrote:
>
> The lower the resistance in the wire, the better.  Stranding vs. unstranded
only makes a difference if the resistance is lower.  Litz wire should be
excellent.  A loop made of monster speaker wire is probably better for the same
size.  Copper plumbing pipe - the 1/4 inch type, would probably be even better. 
Low resistance = high Q = good loop.  But bigger loops are always better, they
can eclipse the choice of wire.

Years ago, I found a huge spool of #16 stranded at a hamfest. Stranded trumps
solid any day of the week - construction-wise. My MW 1m square loop of ten turns
@ .5" spacing and tuned with a dual 365/409 pF variable cap and a single
coupling turn 6" in from the tuned turns - and fed via zipcord to a 1:1 balun
then the RG-58 to my receivers. I used it for my TTFD, too. Still a bunch
left... great for construction - Litz wouls be better.

I am toying with the idea of recycling my 'Monster' speaker cables - twin large
Litz-looking wires - as single/dual turn Tropical Band tuned loops - maybe 1 or
2 turns on a .7 - 1 meter form - tuned with a 3 gang variable cap. The problem
is making a coax impedance tap on the turn(s) - how can I do that with the
'Monster' cable... isn't it a Litz-like wire?

John

PS The multi-turns of #16 stranded on the MW loop - and a newer smaller version
- have wooden 'spreaders' weaved through them to take up the inevitable 'droop'
stranded wire gets... a common malady with advancing age! The TTFD just worked
better at lower frequencies...

--- In loopantennas@yahoogroups.com, "zehelmer" <zehelmer@...> wrote:
> Hi,
>
> Jetpilot, the translator is just funny ;-)

Going from Portuguese to English is even funnier!
We have simple phrases to say it in English. ;-)


>> who are the two beautiful woman?
> what is the woman two beautiful?

Woman, Ladies, Girls, Females.... Chicas
In your post, you gave a link to pictures.
In one of those pictures were two woman.
The two woman were standing, arms out pointing.
They were pointing to a poster display on the wall, for an antenna.
You don't know what I am talking about?

Cheers

At 09:17 PM 12/1/2009 +0000, you wrote:
>
>
>The lower the resistance in the wire, the better. Stranding vs. unstranded
>only makes a difference if the resistance is lower. Litz wire should be
>excellent. A loop made of monster speaker wire is probably better for the
>same size. Copper plumbing pipe - the 1/4 inch type, would probably be
>even better. Low resistance = high Q = good loop. But bigger loops are
>always better, they can eclipse the choice of wire.


I suppose Litz wire could be called stranded wire ... but a very special
kind.  The 'skin effect'  controls the RF conductivity of
materials.  Simply stranding un insulated strands of copper wire ... as is
usual in normal stranded wire does not improve conductivity to the same
degree as individually insulated strands ... as is the case with Litz type
wire.  it is possible to make your own Litz-like wire by stranding light
gauge enameled wire.  The enamel insulation is quite durable.

The main purpose of stranding un insulated copper is to provide strength
and flexibility .... whereas the purpose of stranding insulated copper wire
(as in Litz) is to improve the RF conductivity for a given wire
guage.  monster speaker wire may provide great flexibility and conductivity
for DC & AF purposes ... but is nothing special when dealing with RF.

73

Jim, VE3CI

I have recently found and lost a construction article on 20 meter TX small loop
made from hard line coax. The author did not use tuning capacitor. The loop was
tuned to frequency using old fashioned gimmick capacitor made from twisting
wires together.  Does anybody in this group knows what article I am talking
about? Google is no help!
Thanks for reading  73 Vaclav AA7EJ
 




[Non-text portions of this message have been removed]

At 08:29 PM 12/1/2009 +0000, you wrote:
>
>
>Hi,
>
>Considering the windinds process for air coil loop, I have being using
>enameled copper wire.
>
>I have seen lots of loop projects basically using standard stranded wire,
>instead of the magnetic wire used mainly in transformers.
>
>My initial post is about litz wire in ferrite loops, but both subjects are
>interconnected.
>
>I haven´t found yet a source proving in practical terms what´s the best
>material to achieve higher performance on MW (abstracting Litz wire for RF).
>
>Does anyone has observed any practical differences in such approaches ?
>
>Thks
>Sarmento - Rio de Janeiro - Brazil

Hi Sarmento,

Generally speaking when one wants to construct a tuned loop - or any other
tuned circuit - with highest possible Q one wants to use the best design
and material that will present the least amount of resistance to RF
currents in the inductor.  The two factors that inhibit RF conductivity are
'skin effect' and 'proximity effect'.

Skin effect (RF conducts on the surface area) is overcome by using wire
with the largest diameter possible .... or using multiple strands ... each
insulated from the other.   Ordinary stranded wire is not an improvement
... in fact it may be a poorer RF conductor than the equivalent diameter
solid wire.

The other factor 'proximity effect' is the result of induced eddy current
as one conductor is brought within the electrical field of another
conductor that is carrying current.  The resultant eddy currents inhibit RF
current flow.  Ideally it is a good idea to keep each turn out of the
electrical field of the other.

1. strategy would be to use large conductors ... such as copper tubing in
order to limit 'skin effect'... and to allow wide spacing between turns to
limit the 'proximity' effect.  This strategy is possible when space and
maneuverability is not an issue.

2. strategy is to use High Quality Litz wire .... which uses multiple
insulated strands to limit 'skin effect' arranged in a special
'weave'  (not all Litz wire are equal) to limit 'proximity effect'.  This
is best used effectively in projects with space limitations.  By the way,
special 'weaving' techniques can be used when actually winding your loop or
coil.  If you are going to construct a large loop with wide spacing then
Litz wire will bring minimal returns.  However if your inductor is small
with tight winding on an iron core then Litz wire can be worth it's weight
in gold .... good thing Litz wire is light hi hi.

The first strategy is limited to scenarios where there is no limit on size
and weight.  The second strategy is used where there are great limits on
size and weight.

If you want to see dramatic examples of these two techniques do a search on
crystal radio construction.  Crystal Radio aficionados strive for tuned
circuits with maximum Q .... essential since the rule is that all power
comes from the received signal only .... no electronic amplification
allowed !!   I have seen crystal radio coils the size of 45 gallon drums !!

When trying to eke out the nth degree of efficiency the quality of the
tuning capacitor can be a considerable factor ... but that is another story.

I have built any number of crystal radio receivers and found the same
techniques for winding receiver coils are directly transferable to winding
tuned loop antennas.

Jim, VE3CI

The only difference making a 20M magnetic transmitting loop with a gimmick
capacitor is no different than using a regular capacitor, I have done both. 
Only use the gimmick capacitor if you intend to use low power (QRP).

Here is a link you will find interesting that uses both a gimmick capacitor and
hardline for a compact loop:

http://www.antennex.com/hws/ws0902/hardline.html

I have built the above using 7/8" aluminum hardline and it does work with powers
up to about 20watts.

Andrew
N3LCW


--- In loopantennas@yahoogroups.com, vaclav sal <vaclav_sal@...> wrote:
>
> I have recently found and lost a construction article on 20 meter TX small
loop made from hard line coax. The author did not use tuning capacitor. The loop
was tuned to frequency using old fashioned gimmick capacitor made from twisting
wires together.  Does anybody in this group knows what article I am talking
about? Google is no help!
> Thanks for reading  73 Vaclav AA7EJ
>  
>
>
>
>
> [Non-text portions of this message have been removed]
>

Jim Dunstan wrote:
(snip)
> The other factor 'proximity effect' is the result of induced eddy current
> as one conductor is brought within the electrical field of another
> conductor that is carrying current.  The resultant eddy currents inhibit RF
> current flow.  Ideally it is a good idea to keep each turn out of the
> electrical field of the other.
(snip)

All good stuff, except that I think proximity effect
involves the magnetic field of nearby conductors, not the
electric field.

Here is the most useful tutorial I have found on winding and
wiring eddy current losses, including proximity effect losses.
http://focus.ti.com/lit/ml/slup197/slup197.pdf

I'll put a link to this document on the link section for
this group.

--
Regards,

John Popelish

At 05:16 PM 12/2/2009 -0500, you wrote:
>
>
>Jim Dunstan wrote:
>(snip)
> > The other factor 'proximity effect' is the result of induced eddy current
> > as one conductor is brought within the electrical field of another
> > conductor that is carrying current. The resultant eddy currents inhibit RF
> > current flow. Ideally it is a good idea to keep each turn out of the
> > electrical field of the other.
>(snip)
>
>All good stuff, except that I think proximity effect
>involves the magnetic field of nearby conductors, not the
>electric field.
>
>Here is the most useful tutorial I have found on winding and
>wiring eddy current losses, including proximity effect losses.
><http://focus.ti.com/lit/ml/slup197/slup197.pdf>http://focus.ti.com/lit/ml/slup\
197/slup197.pdf
>
>I'll put a link to this document on the link section for
>this group.
>
>--
>Regards,
>
>John Popelish


   Hi,

You are correct ... a slip of the grey matter ... the magnetic fields are
the fields of concern in this scenario.

Jim, VE3CI




[Non-text portions of this message have been removed]

At 04:10 PM 12/2/2009 -0500, you wrote:
>Hi Jim, What would be the ideal antenna tuned for560 Am.  I live 70 Mi.
>from station and get a lot of noise, At night its impossible to hear. I
>have built 4 ft square shielded and unshielded, also wrapped a 1 foot
>ferrite in 600 strand litz wire  and shielded it with slitted tube gaining
>limited success. I have purchased a Sangean hdt-1 hd radio but can't get
>enough signal to it. Thank You, Alexis.


Hi Alexis,

Are the loops you describe (the 4' and the ferrite rod version) tuned ?  I
am not familiar with the HDT-1 other than it is a HI-FI component generally
installed in close proximity to your sound system.  I believe it has a rear
connection for an external AM antenna.  As consequence you will have to
provide some system of coupling from the tuned loop to the antenna input
connection on the radio.

You have the problem that the signal from the 560khz station is not strong
enough in relation the local noise.  If I am correct the HDT-1 is not very
portable.  You mention shielding the loop.  Shielding the loop (in my
opinion) will not lower the noise .... let alone raise the 560 signal strength.

Increasing the listen ability of the setup will require the loop be
tuneable, and be coupled to the radio by a lengthy feed line.  The higher
the loop Q ... the sharper it tunes and the better the quality the more it
will increase the signal in relation to received background noise.  The
reason for the lengthy feed line is that it will allow you to locate the
loop within the room to a spot with the least RF noise and best
reception.  If you were using a portable radio ... your best strategy would
be to take both the radio and loop to a quiet location ... e.g. like out on
the patio deck hi hi.

you need a quality tuned loop (shielding is irrelevant) .... it has to be
designed with a coupling loop and feed line.   You tune and locate the loop
for best reception.  You will be surprised how much difference there is in
RF noise from one location a few feet from another.  Of course orienting
the loop for minimal noise will be part of the process.

Just a side light ... I have a component receiver which came with a small
(8" 4 turn untuned loop) as the AM antenna.  I made a small tuned loop
(approx 1 ft square) tuned with a 365 pfd capacitor.  I then used the small
4 turn loop as a coupling loop (just mounted it on the same frame as the
tuned loop).  The feed line from the coupling loop was simply a twisted
pair of wire.... which i lengthened to about 10 ft.  I would then locate
the tuned loop for best reception.  The untuned loop provided by the radio
manufacturer was only effective for strong local AM stations.  the
arrangement dramatically improved reception .... but still not as good as a
portable out on the deck hihi.

Jim

Hi,
     An interesting posting on loop antennas.
I came across some speaker wire advertised in the UK at £35 / metre ( $63 )
when I saw a sample it was like the wire you see on welding sets, 15mm dia
jacket
and hundreds of fine strands, would this do a one turn loop ?????
                                            72, Brian, G0NSL-QRP.

   ----- Original Message -----
   From: jrtow3rd@...
   To: loopantennas@yahoogroups.com
   Sent: Wednesday, December 02, 2009 1:09 PM
   Subject: [loopantennas] Re: Stranded copper wire versus magnetic wire
(enameled)




[Non-text portions of this message have been removed]

Grundig YB-300PE AM/FM/SW Receiver + Tecsun AN-200 MW Loop Antenna Package.

Both the radio and loop antenna are LNIB and come with all original accessories,
packaging and manuals. Items are in mint condition, both operationally and
physically, and were well-cared for and in a smoke-free environment. Shipped
double-boxed and well-packed.

$60 + actual shipping (your choice). Paypal preferred.

Honor and integrity mean everything to me- check out my feedback on ebay (ID=
vectorczar).

Email me:  KI4NEJ@...

Thanks,

Lee

How do you feed a loop balanced?

With what kind of a coaxial can it be possible, with two separate coaxial cables
or with one with 2 inner wires? I happen to possess the latter type.

If I would use normal speaker-double-wire, would it not give me all kinds of
electric disturbance?

With the special coaxial with 2 inner wires, would they not disturb each other?

Best Regards from Aimo

--- On Tue, 11/10/09, Chris Trask <christrask@...> wrote:

From: Chris Trask <christrask@...>
Subject: Re: [loopantennas] Loops null direction
To: loopantennas@yahoogroups.com
Date: Tuesday, November 10, 2009, 11:36 PM






 









       When the loop is fed balanced, the null is ALWAYS perpendicular to the

plane of the antenna.



If you feed it unbalanced, the null moves, or rather diminishes.  As you

approach the first parallel resonance, the resonance the null will disappear

entirely.  Above the first parallel resonance, the null will return to being

perpendicular to the plane of the antenna, but the phase will be reversed.

As you approach the first series resonance (between the first and second

parallel resonances), the pattern will rotate.



I learned this while doing extensive ELNEC/EZNEC simluations of

single-turn loops for my 2-part series on active loop antennas in the March

2007 issue of QEX.  I did it to emphasize the point that loop antennas

should ALWAYS be fed balanced.



Chris





 






[Non-text portions of this message have been removed]

Chris,

I think Aimo may be asking about feeding with Twinaxial cable.  I'm kind of
curious about that myself.  I have tons of twinax laying around from an as/400
de-installation.

Regards,
Kenn
KA5KXW


--- In loopantennas@yahoogroups.com, aimo ruoho <aimounto@...> wrote:
>
> How do you feed a loop balanced?
>
> With what kind of a coaxial can it be possible, with two separate coaxial
cables or with one with 2 inner wires? I happen to possess the latter type.
>
> If I would use normal speaker-double-wire, would it not give me all kinds of
electric disturbance?
>
> With the special coaxial with 2 inner wires, would they not disturb each
other?
>
> Best Regards from Aimo
>
> --- On Tue, 11/10/09, Chris Trask <christrask@...> wrote:
>
> From: Chris Trask <christrask@...>
> Subject: Re: [loopantennas] Loops null direction
> To: loopantennas@yahoogroups.com
> Date: Tuesday, November 10, 2009, 11:36 PM
>
> should ALWAYS be fed balanced.
>
>
>
> Chris
>

>
> I think Aimo may be asking about feeding with Twinaxial cable.  I'm kind
> of curious about that myself.  I have tons of twinax laying around from
> an as/400 de-installation.
>

     You won't ba able to use Twinax by itself as you'll have a tremendous
impedance mismatch. Somewhere, you will need a matching section (single
frequency) and, if using coax, a BalUn transformer.

Chris

      ,----------------------.       High Performance Mixers and
     /    What's all this     \    Amplifiers for RF Communications
    / extinct stuff, anyhow?  /
    \  _______,--------------'           Chris Trask / N7ZWY
   _ |/                                  Principal Engineer
  oo\                                  Sonoran Radio Research
(__)\       _                             P.O. Box 25240
   \  \    .'  `.                     Tempe, Arizona 85285-5240
    \  \  /      \
     \  '"        \                 IEEE Senior Member #40274515
      .       (  ) \
       '-| )__| :.  \              Email: christrask@...
         | |  | | \  '.       http://www.home.earthlink.net/~christrask
        c__; c__;  '-..'>.__

                        Graphics by Loek Frederiks

At 10:19 PM 12/9/2009 +0000, you wrote:
>
>
>How do you feed a loop balanced?
>
>With what kind of a coaxial can it be possible, with two separate coaxial
>cables or with one with 2 inner wires? I happen to possess the latter type.
>
>If I would use normal speaker-double-wire, would it not give me all kinds
>of electric disturbance?
>
>With the special coaxial with 2 inner wires, would they not disturb each
>other?
>
>Best Regards from Aimo

Hi Aimo,

by definition, a balanced antenna is symmetrical ... physically and
electrically and does not require ground/earth as a counter-poise. The feed
point is in the middle as far as the dipole/doublet is concerned and
anywhere in the circumference of a loop.   the radiation pattern of
balanced antennas depends on the maintenance of electrical symmetry in
addition to its mechanical symmetry. The electrical symmetry can be
affected by objects (usually metal) in the vicinity of the antenna's
magnetic field and/or the structure of the feed system.

Your question relates to the feed system of a balanced antenna and the
maintenance of antenna balance.  There are 2 connections at the feed point
which should always be equal but opposite at any point in time -
electrically speaking.  A 2 wire feed line is ideal in this respect ...
such as speaker cable, TV twinlead, twisted pair, etc.

You mention 'disturbance' .... I am not quite sure what you are referring
to.  If you mean that the feed line is picking up signals in addition to
the antenna ... then you should not be concerned.  A 2 wire symmetrical
feed line such as 75 or 300 ohm twin lead if connected to a balanced
antenna and a balanced input at the receiver will not add any signals
picked up by the feed line to the signals picked up by the antenna.  The
reason is that the conductors pickup antenna currents as if they were 1
wire and the currents cancel at the antenna and at the receiver input ...
leaving only the antenna currents fed to the line by the antenna.

As soon as you use coaxial cable you introduce a balance problem.  The
problem being that the advertised cable ratings are those between the
center conductor and the inside of the shield.  However, if precautions are
not taken to isolate the inside of the cable shield from the outside then
antenna currents will flow on the outside of the feed line and mix with the
currents from the antenna.  The irony of this is that the coax feed line
will pickup more 'disturbance'  than a simple unshielded pair !!

The second major concern when designing an antenna feed line system is
matching and feed line efficiency.  That is getting as much of the antenna
signal to the radio via the feed line/and or amplifier .... which is quite
a different matter to the concern for balance.

Jim

Thanks, Chris!
I do not know the impedance of my Twinaxial cable.
What kind of a matching section would you suggest?

I have used Twinaxial as a loop on my inner wall, and it gives a rather good
signal when an A.T.U is used between it and my Ten-Tec RX340.
I also use it between my 75 Ohm Loop and A:T.U. with much equal results.
Both systems give me very good signals with the same stations as my other
antennas on the roof, an 8-wire, 3-wire, Broom Stick, DX 1 Prof. MK 2 and
Wellbrook 100M!!!!!! All of the mentioned are downloaded with coaxial cables,
either 50 Ohm or 75 Ohm.

What might be wrong here in Spain to me not being able to listen to real DX?
I mean the low powered broadcasting stations of the world, which are very well
heard in Finland. I will not move to the cold northern countries any more! But I
really would like to continue this best hobby of the world....

Best Regards from a frustrated Dxista.
Aimo

--- On Thu, 12/10/09, Chris Trask <christrask@...> wrote:

From: Chris Trask <christrask@...>

        
         





    .





















[Non-text portions of this message have been removed]

Interesting - I found 3 different impedance references for twinas - 78, 95, 100
Ohms.

http://www.amphenolrf.com/products/twinax.asp?N=0&sid=4B258000A4B617F&

http://www.connectworld.net/tms/0-CAB-TWINAX-PL.html

Probably will have to research impedance by working off of cable part number
before deciding on proper impedance transformation. Then again, if you are
connecting the conductors in parallel (tying together at each end) or in series
creating a continuous coil of 2 turns, you should not have to worry about
characteristic impedance for connecting to a feedline to your radio. I would
think that the capacitance between conductors in series would go more towards
frequency resonance calculations.

73,
kevin
kc6pob

--- On Sat, 12/12/09, aimo ruoho <aimounto@...> wrote:

From: aimo ruoho <aimounto@...>
Subject: Re: [loopantennas] Re: Loops null direction
To: loopantennas@yahoogroups.com
Date: Saturday, December 12, 2009, 2:02 PM







 









       Thanks, Chris!

I do not know the impedance of my Twinaxial cable.

What kind of a matching section would you suggest?



I have used Twinaxial as a loop on my inner wall, and it gives a rather good
signal when an A.T.U is used between it and my Ten-Tec RX340.

I also use it between my 75 Ohm Loop and A:T.U. with much equal results.

Both systems give me very good signals with the same stations as my other
antennas on the roof, an 8-wire, 3-wire, Broom Stick, DX 1 Prof. MK 2 and
Wellbrook 100M!!!!!! All of the mentioned are downloaded with coaxial cables,
either 50 Ohm or 75 Ohm.



What might be wrong here in Spain to me not being able to listen to real DX?

I mean the low powered broadcasting stations of the world, which are very well
heard in Finland. I will not move to the cold northern countries any more! But I
really would like to continue this best hobby of the world....



Best Regards from a frustrated Dxista.

Aimo



--- On Thu, 12/10/09, Chris Trask <christrask@earthlin k.net> wrote:



From: Chris Trask <christrask@earthlin k.net>



 

         



    .



[Non-text portions of this message have been removed]

























[Non-text portions of this message have been removed]

Thank you ever so much for the information, Kevin.
I wonder, when I will be able to use the Wikipedia Free Dictionary more(?).
I always forget it and make public questions in the groups instead...
Best Regards!
Aimo

--- On Mon, 12/14/09, kevin asato <kc6pob@...> wrote:

From: kevin asato <kc6pob@...>
Subject: Re: [loopantennas] Re: Loops null direction
To: loopantennas@yahoogroups.com
Date: Monday, December 14, 2009, 6:28 AM







 









       Interesting - I found 3 different impedance references for twinas - 78,
95, 100 Ohms.



http://www.amphenol rf.com/products/ twinax.asp? N=0&sid=4B258000 A4B617F&



http://www.connectw orld.net/ tms/0-CAB- TWINAX-PL. html



Probably will have to research impedance by working off of cable part number
before deciding on proper impedance transformation. Then again, if you are
connecting the conductors in parallel (tying together at each end) or in series
creating a continuous coil of 2 turns, you should not have to worry about
characteristic impedance for connecting to a feedline to your radio. I would
think that the capacitance between conductors in series would go more towards
frequency resonance calculations.



73,

kevin

kc6pob



--- On Sat, 12/12/09, aimo ruoho <aimounto@yahoo. com> wrote:



From: aimo ruoho <aimounto@yahoo. com>

Subject: Re: [loopantennas] Re: Loops null direction

To: loopantennas@ yahoogroups. com

Date: Saturday, December 12, 2009, 2:02 PM



 



Thanks, Chris!



I do not know the impedance of my Twinaxial cable.



What kind of a matching section would you suggest?



I have used Twinaxial as a loop on my inner wall, and it gives a rather good
signal when an A.T.U is used between it and my Ten-Tec RX340.



I also use it between my 75 Ohm Loop and A:T.U. with much equal results.



Both systems give me very good signals with the same stations as my other
antennas on the roof, an 8-wire, 3-wire, Broom Stick, DX 1 Prof. MK 2 and
Wellbrook 100M!!!!!! All of the mentioned are downloaded with coaxial cables,
either 50 Ohm or 75 Ohm.



What might be wrong here in Spain to me not being able to listen to real DX?



I mean the low powered broadcasting stations of the world, which are very well
heard in Finland. I will not move to the cold northern countries any more! But I
really would like to continue this best hobby of the world....



Best Regards from a frustrated Dxista.



Aimo



--- On Thu, 12/10/09, Chris Trask <christrask@ earthlin k.net> wrote:



From: Chris Trask <christrask@ earthlin k.net>



 



  



    .



[Non-text portions of this message have been removed]



[Non-text portions of this message have been removed]

























[Non-text portions of this message have been removed]

Has anyone had any experience with the large ferrite rods and loops offered at
stormwise.com?  They look like they have some nice toys to play around with?

Frank in Boston

They do have some neat stuff.

They have single gang air variable caps for $18 - duals for $40. Times have
changed - I haven't seen them anywhere in a while. I remember driving down to to
Chicago to EDI discount electronic stores in the summer/autumn of '69. I was in
a USN ET A3/A4 school - shipboard indoctrination - actually schooled on the
R390A. Anyhow, they had boxes of those single gang air variables - rated
365-384-409 pF max - $.19! Looked identical, of course. I think the dual gangs
were $1. I knew I should have bought more!

Seriously high prices... but where can you find ferrite rods now? Does Amidon
still sell them?

John

Hi !

Some time ago I bought variable capacitors from Bebek ltd, Finland.

10 euros/piece.

http://www.bebek.fi/kauppa/index2.php

You can make web orders also, reliable shop.

Unfortunately web pages are in Finnish, but finnish word "säätökondensaattorit"
= variable condensators.

BR





> To: loopantennas@yahoogroups.com
> From: JRTOW3RD@...
> Date: Tue, 15 Dec 2009 12:15:44 +0000
> Subject: [loopantennas] Re: Storwise Loops
>
> They do have some neat stuff.
>
> They have single gang air variable caps for $18 - duals for $40. Times have
changed - I haven't seen them anywhere in a while. I remember driving down to to
Chicago to EDI discount electronic stores in the summer/autumn of '69. I was in
a USN ET A3/A4 school - shipboard indoctrination - actually schooled on the
R390A. Anyhow, they had boxes of those single gang air variables - rated
365-384-409 pF max - $.19! Looked identical, of course. I think the dual gangs
were $1. I knew I should have bought more!
>
> Seriously high prices... but where can you find ferrite rods now? Does Amidon
still sell them?
>
> John
>
>
>
> ------------------------------------
>
> If you've got links, post them in the Links section!
> http://groups.yahoo.com/group/loopantennas/links
>
> Post files here. If the file comes from a website, please put it in the Links
rather than uploading the file.
> http://groups.yahoo.com/group/loopantennas/files
>
> You can now view images at higher resolution in Photos. Upload JPG and GIF
into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
> http://ph.groups.yahoo.com/group/loopantennas/photos
>
> And please trim all this when replying!Yahoo! Groups Links
>
>
>

_________________________________________________________________
Windows Live: Make it easier for your friends to see what you’re up to on
Facebook.
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network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_2:092009

[Non-text portions of this message have been removed]

Rapid Xmas delivery if ordered through Lapland agent.......

--- On Tue, 15/12/09, Notareal <not_a_real@...> wrote:

From: Notareal <not_a_real@...>
Subject: RE: [loopantennas] Re: Storwise Loops; VARIABLE CAPACITORS AVAILABLE !
To: loopantennas@yahoogroups.com
Date: Tuesday, 15 December, 2009, 13:25


Hi !

Some time ago I bought variable capacitors from Bebek ltd, Finland.

10 euros/piece.

http://www.bebek.fi/kauppa/index2.php

You can make web orders also, reliable shop.

Unfortunately web pages are in Finnish, but finnish word
"säätökondensaattorit" = variable condensators.

BR





> To: loopantennas@yahoogroups.com
> From: JRTOW3RD@...
> Date: Tue, 15 Dec 2009 12:15:44 +0000
> Subject: [loopantennas] Re: Storwise Loops
>
> They do have some neat stuff.
>
> They have single gang air variable caps for $18 - duals for $40. Times have
changed - I haven't seen them anywhere in a while. I remember driving down to to
Chicago to EDI discount electronic stores in the summer/autumn of '69. I was in
a USN ET A3/A4 school - shipboard indoctrination - actually schooled on the
R390A. Anyhow, they had boxes of those single gang air variables - rated
365-384-409 pF max - $.19! Looked identical, of course. I think the dual gangs
were $1. I knew I should have bought more!
>
> Seriously high prices... but where can you find ferrite rods now? Does Amidon
still sell them?
>
> John
>
>
>
> ------------------------------------
>
> If you've got links, post them in the Links section!
> http://groups.yahoo.com/group/loopantennas/links
>
> Post files here. If the file comes from a website, please put it in the Links
rather than uploading the file.
> http://groups.yahoo.com/group/loopantennas/files
>
> You can now view images at higher resolution in Photos. Upload JPG and GIF
into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
> http://ph.groups.yahoo.com/group/loopantennas/photos
>
> And please trim all this when replying!Yahoo! Groups Links
>
>
>
                           
_________________________________________________________________
Windows Live: Make it easier for your friends to see what you’re up to on
Facebook.
http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-\
network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_2:092009

[Non-text portions of this message have been removed]



------------------------------------

If you've got links, post them in the Links section!
http://groups.yahoo.com/group/loopantennas/links

Post files here. If the file comes from a website, please put it in the Links
rather than uploading the file.
http://groups.yahoo.com/group/loopantennas/files

You can now view images at higher resolution in Photos. Upload JPG and GIF into
Photos. Please convert BMP or TIF to JPG or GIF before uploading.
http://ph.groups.yahoo.com/group/loopantennas/photos

And please trim all this when replying!Yahoo! Groups Links





[Non-text portions of this message have been removed]

I've ordered a couple of 13.5" 125u rods, and made a really nice tuned ferrite
rod antenna for MW dxing. works very well. I used Litz wire to do the windings.
Very sharp tuning, and when inductively coupled to the ferrite on several
radios, truly enhances the signals. I'm thinking of doing up a nice LW antenna
for NDB Dxing with my R75, using a coupling section to input into the high Z in
the radio...

THese rods are fantastic.

Darren
VE6IZ

[Non-text portions of this message have been removed]

>
> I've ordered a couple of 13.5" 125u rods, and made a really nice tuned
> ferrite rod antenna for MW dxing. works very well. I used Litz wire to
> do the windings. Very sharp tuning, and when inductively coupled to the
> ferrite on several radios, truly enhances the signals. I'm thinking of
> doing up a nice LW antenna for NDB Dxing with my R75, using a coupling
> section to input into the high Z in the radio...
>
> THese rods are fantastic.
>

     I used a similar rod for my active ferrite rod antenna, using a somewhat
novel approach to the remote tuning which provides a much higher signal
voltage to the amplifier:

     http://www.home.earthlink.net/~christrask/Paper006.html

Chris

My Dear Friend, my keyboard will not let me put in those letter as is in your
lang, so maybe you could do a better link to there caps page. Thank You. Mike
UK. --- In loopantennas@yahoogroups.com, Notareal <not_a_real@...> wrote:
>
>
> Hi !
>
> Some time ago I bought variable capacitors from Bebek ltd, Finland.
>
> 10 euros/piece.
>
> http://www.bebek.fi/kauppa/index2.php
>
> You can make web orders also, reliable shop.
>
> Unfortunately web pages are in Finnish, but finnish word
"säätökondensaattorit" = variable condensators.
>
> BR
>
>
>
>
>
> > To: loopantennas@yahoogroups.com
> > From: JRTOW3RD@...
> > Date: Tue, 15 Dec 2009 12:15:44 +0000
> > Subject: [loopantennas] Re: Storwise Loops
> >
> > They do have some neat stuff.
> >
> > They have single gang air variable caps for $18 - duals for $40. Times have
changed - I haven't seen them anywhere in a while. I remember driving down to to
Chicago to EDI discount electronic stores in the summer/autumn of '69. I was in
a USN ET A3/A4 school - shipboard indoctrination - actually schooled on the
R390A. Anyhow, they had boxes of those single gang air variables - rated
365-384-409 pF max - $.19! Looked identical, of course. I think the dual gangs
were $1. I knew I should have bought more!
> >
> > Seriously high prices... but where can you find ferrite rods now? Does
Amidon still sell them?
> >
> > John
> >
> >
> >
> > ------------------------------------
> >
> > If you've got links, post them in the Links section!
> > http://groups.yahoo.com/group/loopantennas/links
> >
> > Post files here. If the file comes from a website, please put it in the
Links rather than uploading the file.
> > http://groups.yahoo.com/group/loopantennas/files
> >
> > You can now view images at higher resolution in Photos. Upload JPG and GIF
into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
> > http://ph.groups.yahoo.com/group/loopantennas/photos
> >
> > And please trim all this when replying!Yahoo! Groups Links
> >
> >
> >
>
> _________________________________________________________________
> Windows Live: Make it easier for your friends to see what you're up to on
Facebook.
>
http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-\
network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_2:092009
>
> [Non-text portions of this message have been removed]
>

> My Dear Friend,

   copy and paste?

Hello!

What kind of variable capacitors do you want?
Let me know exactly, and I will try to contact Bebek for you.
Please, give a perfect list, so I will be able to ask Bebek,
if they still have those variable capacitors.

Another rather inexpencive source is in Lithuania:

Gintaras Sakenas, P.O.Box 1367, Vilnius, LT-2056, Lithuania

I have purchased many different parts from this Radio Amateur,
who is a very reliable and fast source, who packs the parts really well. His
prices are very low...

Aimo

--- In loopantennas@yahoogroups.com, "Mike" <michaelrae65@...> wrote:
>
>
>
> My Dear Friend, my keyboard will not let me put in those letter as is in your
lang, so maybe you could do a better link to there caps page. Thank You. Mike
UK. --- In loopantennas@yahoogroups.com, Notareal <not_a_real@> wrote:
> >
> >
> > Hi !
> >
> > Some time ago I bought variable capacitors from Bebek ltd, Finland.
> >
> > 10 euros/piece.
> >
> > http://www.bebek.fi/kauppa/index2.php
> >
> > You can make web orders also, reliable shop.
> >
> > Unfortunately web pages are in Finnish, but finnish word
"säätökondensaattorit" = variable condensators.
> >
> > BR
> >
> >
> >
> >
> >
> > > To: loopantennas@yahoogroups.com
> > > From: JRTOW3RD@
> > > Date: Tue, 15 Dec 2009 12:15:44 +0000
> > > Subject: [loopantennas] Re: Storwise Loops
> > >
> > > They do have some neat stuff.
> > >
> > > They have single gang air variable caps for $18 - duals for $40. Times
have changed - I haven't seen them anywhere in a while. I remember driving down
to to Chicago to EDI discount electronic stores in the summer/autumn of '69. I
was in a USN ET A3/A4 school - shipboard indoctrination - actually schooled on
the R390A. Anyhow, they had boxes of those single gang air variables - rated
365-384-409 pF max - $.19! Looked identical, of course. I think the dual gangs
were $1. I knew I should have bought more!
> > >
> > > Seriously high prices... but where can you find ferrite rods now? Does
Amidon still sell them?
> > >
> > > John
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > If you've got links, post them in the Links section!
> > > http://groups.yahoo.com/group/loopantennas/links
> > >
> > > Post files here. If the file comes from a website, please put it in the
Links rather than uploading the file.
> > > http://groups.yahoo.com/group/loopantennas/files
> > >
> > > You can now view images at higher resolution in Photos. Upload JPG and GIF
into Photos. Please convert BMP or TIF to JPG or GIF before uploading.
> > > http://ph.groups.yahoo.com/group/loopantennas/photos
> > >
> > > And please trim all this when replying!Yahoo! Groups Links
> > >
> > >
> > >
> >
> > _________________________________________________________________
> > Windows Live: Make it easier for your friends to see what you're up to on
Facebook.
> >
http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-\
network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_2:092009
> >
> > [Non-text portions of this message have been removed]
> >
>