Longwire balun. Which type?
MC
attached directly to my 100+ feet of longwire. As I still want to suck that
little extra out of my antenna, I want to add a balun but I am confused with
this transformer ratio stuff. I realise that a long wire has quite a high
impedance. However, should I go for a 1:4 or a 1:10 ratio balun. If I went
for the 1:10 would it be overkill and will it make any difference over the
RF if I only had a 1:4. I ask because I can get a 1:10 a lot cheaper than a
1:4.
Confused? I am :)
MC
Conan Ford
news:110920488...@spandrell.news.uk.clara.net:
1:9 is ideal for a longwire (ideal impedence is 450 ohms, matched to 50 ohm
coax, so 50:450 = 1:9), so go for the 1:10. The 1:4 is for something with
lower impedence than a longwire.
Not all baluns are created equal, however. What frequencies are they rated
for? This will depend on the turns count of the windings and also on the
ferrite material.
The Axelrods
frequencies.
http://www.angelfire.com/mb/amandx/lim.html
See the above for more info
Shawn
"MC" <notinc...@hotmail.com> wrote in message
news:110920488...@spandrell.news.uk.clara.net...
Howard
wrote:
You may wish to try an ICE matching transformer, they are reasonably
priced and are built well. Another advantage is that you can play
around with the transformation ratio from 6:1, 9:1, 12:1 and 16:1.
http://www.arraysolutions.com/Products/ice/reconly.html#Beverage%20Matching
I would suggest the DC isolation version and you might as well get the
one that goes to 100kHz in case you want to pursue beacons - that
would be model 182A.
Howard
Telamon
Conan Ford <cona...@com.hotmail> wrote:
The impedance of the wire depends on the height above ground. The 1:9 is
most likely best.
--
Telamon
Ventura, California
Conan Ford
news:telamon_spamshield-D142D9.21371823022005@newssvr21-
ext.news.prodigy.
com:
Is there a site that explains this, with a formula that can be used? I
found one once that was for a straight horizontal wire at a fixed
distance above a ground plane, but it wasn't for antennas... I just
assumed 450 ohm was a good value.
Telamon
Conan Ford <cona...@com.hotmail> wrote:
Assuming medium ground conductivity:
Wire impedance = 138 log (4 * height / wire diameter)
Height and wire diameter are in the same units.
An 18 gauge wire 10 foot off the ground would be around 560 ohms.
--
Telamon
Ventura, California
RHF
.
What you call a Longwire Antenna is more generally described as a
Random Wire Antenna; because it is not 'cut' for one frequency and
one or more Wave Lengths (WL) long.
.
For a Shorwave Listener's (SWL) Random Wire Antenna the 'preferred'
lay-out is to have a Long and Elevated Wire Antenna Element that is
connected to a Matching Transformer (near ground level) with a
Ground Rod and Ground; using a Coax Cable Feed-in-Line to the
Radio/Receivers.
.
The 9:1 or 10:1 so called Longwire Balun (Matching Transformer)
UnUn is the 'usual choice' and works well between a Random Wire
Antenna and Coax Cable Feed-in-Line; along with a Grounding Point.
NOTE - A Balun that is 4:1 is usually used with a Dipole or
other type of 'balanced' Antenna.
.
READ - The Magnetic Longwire Balun Question
MLB => http://tinyurl.com/4664f
http://groups-beta.google.com/group/rec.radio.shortwave/msg/a172f950ff3ffe2a
.
THE LONGWIRE BALUN - The best was to make the Antenna Wire to
Coax Cable Connection is to use a Matching Transformer Balun
UnUn or what is called a Magnetic LongWire Balun.
+ These devices make the Electrical-Mechanical (Joints)
Connections between the Antenna Wire Element; the
Ground Wire; and the Coax Cable Feed-in-Line.
+ These devices also help to 'match' the "Impedance" of
the Antenna Wire Element to the Coax Cable Feed-in-Line.
+ These devices provide a "Direct-DC-Ground-Path" for
any Electrical Discharge pasted through the Antenna Wire
Element to earthen ground.
+ The Main Component {Heart} of the Matching Transformer
is the Ferrite Core.
.
* * * Balun Reading List ( Long )
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/337
.
* RF Systems Magnetic Longwire Balun (MLB)
http://www.universal-radio.com/catalog/antsup/1484.html
.
* Shortwave Longwire (10:1) Antenna Feeder #SWL-1
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5745940468
.
* "Universal Magnetic Balun" (UMB) a Receiving (Only)
Antenna Balun with a 9:1 impedance ratio by Wellbrook, UK.
UMB=> http://www.wellbrook.uk.com/UMB.html
.
* Shortwave Longwire Antenna Feeder with balun LWF-1
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5745918363
.
* Magnetic Longwire Balun (MLB) Palomar
http://www.palomar-engineers.com/MLB-1/mlb-1.html
http://www.antennex.com/palomar/page_6.htm
.
* Longwire Isolated (10:1) Antenna Feeder - SWL-1G
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5746411443
.
* WiNRADiO WR-LWA-0130 Long Wire Antenna Adapter
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/230
http://www.grove-ent.com/WR0130.html
http://www.winradio.com/home/lwa.htm
http://www.winradio.com/home/ax05e.htm
.
BUILT YOUR OWN BALUN :
Do-It-Yourself Antenna Balun Kits by ByteMark
http://www.bytemark.com/products/kit_bal1.htm
.
READ - The Inverted "L" Antenna - It's 'basic' Lay-Out and Structure
The Inverted "L" {Shortwave Listerner's} Antenna - "Why-It-Works"
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/1969
http://groups-beta.google.com/group/rec.radio.shortwave/msg/e0b3ddbed819958d
.
.
iane ~ RHF
.
All are WELCOME and "Invited to Join" the
Shortwave Listener (SWL) Antenna eGroup on YAHOO !
<http://groups.yahoo.com/group/Shortwave-SWL-Antenna/>
.
Some Say: On A Clear Day You Can See Forever.
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/502
.
I BELIEVE: On A Clear Night . . .
You Can Hear Forever and Beyond, The BEYOND !
With a Shortwave Listener SWL Antenna of your own making.
"If You Build It {SWL Antenna} You Will Hear Them !"
.
.
David
cuh...@webtv.net
that is ok,I do learn something once in a while.Thanks for that.
cuhulin
David
On 24 Feb 2005 23:04:07 GMT, "-=jd=-" <jd77...@HATpostmark.net>
wrote:
>On Thu 24 Feb 2005 02:03:25a, Telamon
><telamon_s...@pacbell.net.is.invalid> wrote in message
>news:telamon_spamshield-CF0CF3.23032523022005@newssvr21-
>ext.news.prodigy.com:
>There's the rub...
>
>
>> Wire impedance = 138 log (4 * height / wire diameter)
>>
>> Height and wire diameter are in the same units.
>>
>> An 18 gauge wire 10 foot off the ground would be around 560 ohms.
>>
>
>All good advice and well taken, but if someone doesn't have the interest or
>ability to wind their own transformers (to hear the "ear-ball" effects of
>different kinds) and if they don't have a noise-bridge or some way to
>measure/analyze their antenna, then there will always be an element of
>"pure guess" involved to one extent or another. In which case, just get the
>9:1 or 10:1 and be done with it. In other words, for the *average*
>listener, don't sweat the granular details. Just rig something up and start
>listening! Most any random wire/transformer combination (within reason) is
>better than a whip antenna, or something inside the shack. Just my $.02
>worth...
>
>-=jd=-
Conan Ford
news:Xns9607B7EC0E8BD...@63.218.45.20:
>
> All good advice and well taken, but if someone doesn't have the
> interest or ability to wind their own transformers (to hear the
> "ear-ball" effects of different kinds) and if they don't have a
> noise-bridge or some way to measure/analyze their antenna, then there
> will always be an element of "pure guess" involved to one extent or
> another. In which case, just get the 9:1 or 10:1 and be done with it.
> In other words, for the *average* listener, don't sweat the granular
> details. Just rig something up and start listening! Most any random
> wire/transformer combination (within reason) is better than a whip
> antenna, or something inside the shack. Just my $.02 worth...
>
> -=jd=-
It is much cheaper to wind your own transformers--a $5 torroid and $2 of
magnet wire, plus a few connectors and a box. It's either that, or pay up
$40 for a pre-built balun, and you don't know what winding method they used
(or how sloppy it is) since it's all potted in epoxy.
David
On Fri, 25 Feb 2005 02:08:10 GMT, Conan Ford <cona...@com.hotmail>
wrote:
CW
impedance at different frequencies?
"David" <ric...@knac.com> wrote in message
news:p1rr11hkmt5dmhek0...@4ax.com...
David
On Fri, 25 Feb 2005 17:55:07 -0800, "CW" <cma...@earthlink.net>
wrote:
dxAce
David wrote:
> A transmission line is not a generator.
No kidding, 'tard boy.
Go take those meds, and try to be a little more coherent before you post first
thing in the morning.
dxAce
Michigan
USA
CW
David
dependent. Antenna impedance (original question) does have a
frequency component.
On Sat, 26 Feb 2005 18:25:12 -0800, "CW" <cma...@earthlink.net>
wrote:
CW
understand the concept) but it wasn't where the conversation led. Try to
fallow along.
"David" <ric...@knac.com> wrote in message
news:7bq3219gv1ds28o8r...@4ax.com...
David
impedance drops to a value which is dependant on distance from ground.
Away from resonance the impedance goes high. The impedance of a
random wire is largely a function of frequency.
On Sun, 27 Feb 2005 10:58:57 -0800, "CW" <cma...@earthlink.net>
wrote:
RHF
.
The "Impedance" of a Random Wire Antenna is largely a function of :
- The Length of the Wire with respect to the Frequency Specified.
- The Height of the Wire above ground level with respect to the
Frequency Specified.
.
iane ~ RHF
.
Telamon
"RHF" <rhf-new...@pacbell.net> wrote:
> DaviD,
> .
> The "Impedance" of a Random Wire Antenna is largely a function of :
> - The Length of the Wire with respect to the Frequency Specified.
No. The length affects the reactance over frequency.
> - The Height of the Wire above ground level with respect to the
> Frequency Specified.
Yes. The height above ground and the wires diameter.
--
Telamon
Ventura, California
David
dependent.
RHF
.
Antenna = Specific Frequency + Relative Size + Spacial Placement
.
Antenna's do not exist unto themselves : The function {exist} as a
"Mechanism" to 'receive' and/or 'transmit' Radio Frequency Energy.
.
? ? ? What Would Be ? ? ?
The Better Shortwave Antenna (3 MHz - 30 MHz) in Outer Space ?
* A simple Dipole ?
* A basic Longwire ?
[ Where Space is Unlimited -&- The Ground Effect is Nothing ]
.
OBTW - One might also think as a Speaker and/or Microphone as a
form of Antenna 'mechanism' in that they to perform this function
with respect to what is labeled as Audio Frequency Energy.
.
Logic and Reality
- Can Only
- - Come Together
- - - In Our Minds
Now That Requires Thought
.
what more can i say ~ RHF
.
.
David
On 27 Feb 2005 16:24:53 -0800, "RHF" <rhf-new...@pacbell.net>
wrote:
Telamon
"RHF" <rhf-new...@pacbell.net> wrote:
> FO&A - Sorry but my mind is starting to wander and wonder . . .
> .
> Antenna = Specific Frequency + Relative Size + Spacial Placement
> .
> Antenna's do not exist unto themselves : The function {exist} as a
> "Mechanism" to 'receive' and/or 'transmit' Radio Frequency Energy.
Yes they do exist unto themselves. No need for EM wave to be present for
them to exist and they have a characteristic impedance that does not
need any EM waves around either.
An antenna takes or causes or converts a local current loop into
electromagnetic energy on transmit. The antenna performs the reverse
function on receive.
> ? ? ? What Would Be ? ? ?
> The Better Shortwave Antenna (3 MHz - 30 MHz) in Outer Space ?
> * A simple Dipole ?
> * A basic Longwire ?
> [ Where Space is Unlimited -&- The Ground Effect is Nothing ]
Not a lot of difference between air and vacuum. All antennas would work
about the same. They would all resonate at a slightly higher frequency
in vacuum than in air.
> OBTW - One might also think as a Speaker and/or Microphone as a
> form of Antenna 'mechanism' in that they to perform this function
> with respect to what is labeled as Audio Frequency Energy.
Speakers and microphones convert energy between sound pressure waves and
a local current loop. This has nothing to do with electromagnetic waves,
which antennas convert.
> Logic and Reality
> - Can Only
> - - Come Together
> - - - In Our Minds
> Now That Requires Thought
All basic physics.
--
Telamon
Ventura, California
Telamon
David <ric...@knac.com> wrote:
It has nothing to do with frequency. When you are measuring the antennas
reactance to a EM wave then it does but that is not the same thing as
the antennas characteristic impedance.
Get frequency and the reactance to it, out of your head. The impedance
of the antenna or anything else for that matter depends on its physical
properties not what you might stimulate it with.
--
Telamon
Ventura, California