balun question?
vangellis
I'm new to shortwave radio so please bear with me.
I have a Target HF3 receiver (amongst others) that I like to listen to
the Radio Amatuers on.
My antenna at the moment for this radio is a simple 65foot longwire,
that is connected to 50ohm cb coax cable, I have a 50ohm balun in line
and the antenna wire is connected to the one end (the one with a
wingnut on) and the coax is connected via a pl259 plug. I have soldered
a sturdy earth wire on the outer shell of the pl259 and rin it to
ground, that is I have soldered it to the cold water mains input pipe.
Now I was looking at the handbook that came with the HF3 and it states
that the antenna impendance is 75ohm's as it is a simple phono plug on
the back of the radio.
I was wondering if I would get better reception if I took the balun out
altogether and replaced the 50ohm cb coax with tv coax at 75ohm's.
Does anyone have any tips/advise please
thanks
bob
Ian Jackson
<vang...@ntlworld.com> writes
coax from 50 to 75 ohms is unlikely to make a scrap of difference. [Is
it really a balun, or is it (say) a 9:1 transformer (step-down from
antenna to coax)? Such things are used on some receiving systems.]
Note that the antenna impedance of the receiver will only be a 'nominal'
75 ohms, implying that it will be suitable for a low impedance feed from
the antenna (as opposed to 'high' impedance). But it's unlikely to be a
'good' 75 ohms.
--
Ian
RHF
Vangellis,
What you got is good enough -and- there is no need
to change anything in your Set-Up.
Target HF3 AM/SSB Receiver : 30Khz to 30Mhz
http://www.nasamarine.com/Misc/targethf3.html
~ RHF
.
Wimpie
Hello Bob,
For HF, changing to 75 Ohms will not give noticeable improvement.
It is important to also connect the braid to the 3.5mm plug (not to
the center conductor but to the shaft). Grounding the braid outside
your house is OK. It reduces pick-up of interference from other house
hold equipment and (electronic) lighting gear.
I don't know your balun, when it has just one input for the long wire
and a coaxial connection; it is probably just an impedance transformer
(nothing wrong with that).
Make sure that you run your long wire away from sources of
interference.
I checked http://www.mwcircle.org/res-receiver-akd.htm for a review
(Radio Netherlands stopped the receiver reviews). With a 65-foot long
wire, you may experience bad reception because of intermodulation
products (kind of distortion/noise, etc caused by strong transmitters
at other frequencies). Try the attenuator switch on the back of the
receiver, this may give improvement. Best is to let somebody listen
to the receiver that has experience with these types of distortion.
Best regards,
Wim
PA3DJS
www.tetech.nl
remove abc from the mail address.
vangellis
Thank's for your help guys, I appreciate it.
I thought it was a balun! but I took a look at it just now and its a LMZ-50
10:1
50 ohm's to Hi-Z Antenna
I bought it from here about a year ago
http://www.geocities.com/qrp_baluns/LMZ-50.html
cheers
vangellis
vangellis
http://www.geocities.com/qrp_baluns/LMZ-50-Ground.GIF
vangellis
Ian Jackson
<vang...@ntlworld.com> writes
>This link shows how I have "grounded" the setup
>http://www.geocities.com/qrp_baluns/LMZ-50-Ground.GIF
>
>vangellis
>
impedance matching voltage transformer, for 50 ohm coax, and the other
described as a 9:1 voltage balun transformer, for 75 ohm coax. It could
be that they are essentially the same inside (why would they want to
make two different types?), but with different connectors. Neither are
actually acting as baluns (although they be using balun transformers
inside the can).
Some time ago, there was report published of tests which compared the
received signals levels with - and without - this type of transformer.
From memory, it showed that, on most frequencies, there was a very
noticeable increase of signal level into the receiver. Only on a
minority of frequencies was there some (acceptable) reduction of level.
I've had a quick Google, but haven't yet found this report.
--
Ian
RHF
<ianREMOVETHISjack...@g3ohx.demon.co.uk> wrote:
> In message <clbHj.21278$Ff4.12...@newsfe5-win.ntli.net>, vangellis
> <vangel...@ntlworld.com> writes>This link shows how I have "grounded" the setup
> >http://www.geocities.com/qrp_baluns/LMZ-50-Ground.GIF
>
> >vangellis
>
> It's interesting that they have one version which is described as a 10:1
> impedance matching voltage transformer, for 50 ohm coax, and the other
> described as a 9:1 voltage balun transformer, for 75 ohm coax. It could
> be that they are essentially the same inside (why would they want to
> make two different types?), but with different connectors. Neither are
> actually acting as baluns (although they be using balun transformers
> inside the can).
>
- which compared the received signals levels with
- and without - this type of transformer.
- there was a very noticeable increase of signal level
- into the receiver. Only on a minority of frequencies was
- there some (acceptable) reduction of level.
- I've had a quick Google, but haven't yet found this report.
- --
- Ian
IAN,
Read this Post : SWL Longwire + Low Noise Antenna
Connection + Grounding Is Key To Good Reception
Three Messages to Read -by- John Doty
http://groups.google.com/group/rec.radio.shortwave/msg/1abc6a2bf8acc12d
Follow the Links/URLs provided in the Message.
.
~ RHF
.
RHF
Subject-Line was : balun question?
-
- Hi
- Thank's for your help guys, I appreciate it.
- I thought it was a balun!
- but I took a look at it just now and its a LMZ-50
- 10:1 50 ohm's to Hi-Z Antenna
- I bought it from here about a year ago
- http://www.geocities.com/qrp_baluns/LMZ-50.html
-
- cheers
- vangellis
Vangellis,
That is "Jason Erickson" [KG7RO] -aka- RF Junkie's
website about the "QRP" Matching Transformers that
he made back at the time.
http://www.geocities.com/qrp_baluns/contact.html
Notice - Business Closed Dec 2006
"This Site is for Information Purposes Only."
RF JUNKIEs' APPLICATION NOTES :
http://www.geocities.com/qrp_baluns/app-notes.html
How to connect wires to "QB Series" Baluns and Ununs?
Weather-Proofing "QB Series" Baluns and Ununs
SWLZ Application Setup for the Shortwave Listener (SWL)
QB-9E Application Setup for Longwire (SWL and QRP)
QB-10I Application Setup for the Shortwave Listener (SWL)
LMZ-75 Application Setup for Longwire (SWL)
LMZ-50 Application Setup for Longwire (SWL and QRP
QUESTION - WHICH BALUN DO I NEED ?
http://www.geocities.com/qrp_baluns/balun-choice.html
ANTENNA LINK / URLs :
http://www.geocities.com/qrp_baluns/antennas.html
Antenna Basics
The Dipole Antenna
Dipole Calculator
Wire Antennas - Hard Core DX
Rhombic Antenna
G5RV Antenna
Flag / Pennant Antenna Info
K9AY Loop Antenna
Wire Loop Antenna
Windom Antenna
Beverage Antenna
BANDPLANS - THE SHORTWAVE RADIO FREQUENCIES :
http://www.radios4you.com/shortwave-listening.html
Shortwave Listener (SWL) : Longwire / Random Wire :
SWL Antenna Matchers
http://www.geocities.com/qrp_baluns/LM.html
Coax Information : Coaxial Cable Specifications
http://www.rfcafe.com/references/electrical/coax_chart.htm
Got HF Noise Problems ? - Possible Sources Listed Here
http://www.geocities.com/qrp_baluns/SW-noise.html
List of Sources of Shortwave (HF) Noise Problems
Frequently Asked Questions (FAQs)
http://www.geocities.com/qrp_baluns/faq.html
VIA- eHam Reviews for KG7RO Baluns
http://www.eham.net/reviews/detail/4807
REF MSG - RF Junkie 'introduces' new SWLZ Balun
using "F" Connector for use with RG6 Coax Cable
http://groups.google.com/group/rec.radio.shortwave/msg/a9b90bced20caa9d
http://groups.google.com/group/rec.radio.shortwave/msg/b4075493a6e95896
http://groups.google.com/group/rec.radio.shortwave/msg/cd51bcd09158b2a9
IMHO - A Great WebSite - iane ~ RHF
.
RHF
-
- This link shows how I have "grounded" the setup
- http://www.geocities.com/qrp_baluns/LMZ-50-Ground.GIF
-
- vangellis
-
Vangellis,
The "Correct Way" to Install a Longwire Antenna and Balun
by Wellbrook - Using the Far-End Feed-Point Concept
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/11773
The "Correct Way" to Install a Longwire Antenna and Balun
by Wellbrook => http://www.wellbrook.uk.com/longwire.html
We have all most likely done it the wrong way more than once . . .
A key-point that Wellbrook makes is the Five Metre
"Noise Zone" that exists around a House and getting
the Wire Antenna Element away {out} from this area.
http://www.wellbrook.uk.com/longwire.html
Note - The above "Correct Way" installation will ensure
that the Wire Antenna Element is 'outside' the local
Noise Zone which extends up to Five Metres (16 Feet)
around the House. Also the noise pickup is lower with
the feeder close to the ground -or- buried under the
ground a few inches.
-Why- The Antenna and the Balun are within the Local
Noise Zone RFI & EMF {Interference Area} that surrounds
most buildings up to distance of Five Metres (16 Feet).
Read - WHY - The Far-End-Fed Shortwave Listener's
(SWLs) Inverted "L" Antenna
http://groups.google.com/group/rec.radio.shortwave/msg/22cfc6b9cb2447c0
all i ask for is five metres beyond the noise - iane ~ RHF {pomkia}
.
Shortwave Listener (SWL) Antennas Group => http://tinyurl.com/ogvcf
GoTo => http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
RHF's Standard "Shortwave Radio Listener (SWL) Antennas Group"
Reference Message Signature-Line => http://tinyurl.com/25zbrg
http://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
.
-=25ZBRG=-
.
Ian Jackson
<408df09c-2b28-44df...@e6g2000prf.googlegroups.com>, RHF
<rhf-new...@pacbell.net> writes
Thanks. There's certainly a lot of good reading there, and in the links
in your other posts today. The info particularly in
http://web.archive.org/web/20030609000229/www.anarc.org/naswa/badx/antenn
as/SWL_longwire.html
is exactly the sort of thing I was thinking about.
However, there's one thing which I note (just a quick look) on several
of the websites, and that is the transformer is repeatedly referred to
as a 'balun'. It isn't. I suspect that it's because they are using the
same transformer as the type used in a balun but, in this application, a
balun it ain't!
--
Ian
dxAce
Ian Jackson wrote:
transformer/balun. The only ones who care are anal folk like 'Eduardo'.
dxAce
dxAce wrote:
And, as always, don't do business with the Huntington Investment Company.
RHF
<ianREMOVETHISjack...@g3ohx.demon.co.uk> wrote:
> In message
> <408df09c-2b28-44df-a0a6-ff98233c7...@e6g2000prf.googlegroups.com>, RHF
> <rhf-newsgro...@pacbell.net> writes
> as/SWL_longwire.html
>
> is exactly the sort of thing I was thinking about.
- However, there's one thing which I note (just a quick look)
- on several of the websites, and that is the transformer is
- repeatedly referred to as a 'balun'.
-
- It isn't. I suspect that it's because they are using the
- same transformer as the type used in a balun but,
- in this application, a balun it ain't!
- --
- Ian
-
Ian Jackson -read- The Magnetic Long-Wire Antenna Balun
- A Balun It Ain't ! - But It Works :o)
http://groups.google.com./group/rec.radio.shortwave/msg/5a334b2122c8ddbf
iane ~ RHF
.
Telamon
<fbd7c531-51de-4ee5...@u10g2000prn.googlegroups.com>,
RHF <rhf-new...@pacbell.net> wrote:
> > Thanks. There's certainly a lot of good reading there, and in the links
> > in your other posts today. The info particularly in
> >
> > http://web.archive.org/web/20030609000229/www.anarc.org/naswa/badx/an...
> > as/SWL_longwire.html
> >
> > is exactly the sort of thing I was thinking about.
> -
> - However, there's one thing which I note (just a quick look)
> - on several of the websites, and that is the transformer is
> - repeatedly referred to as a 'balun'.
> -
> - It isn't. I suspect that it's because they are using the
> - same transformer as the type used in a balun but,
> - in this application, a balun it ain't!
>
> Ian Jackson -read- The Magnetic Long-Wire Antenna Balun
> - A Balun It Ain't ! - But It Works :o)
>
> http://groups.google.com./group/rec.radio.shortwave/msg/5a334b2122c8ddbf
>
This isn't hard to understand. This is a two part term, which refers to
the type of transformer. "BAL" refers to balanced and "UN" refers to
unbalanced so the possibilities are BALBAL, UNUN, or BALUN.
A long wire is unbalanced and a coax is unbalanced so the transformer
type you would use is a UNUN. If you had a dipole, which is balanced
connected to a coax you would use a BALUN.
--
Telamon
Ventura, California
RHF
<telamon_spamshi...@pacbell.net.is.invalid> wrote:
> In article
> <fbd7c531-51de-4ee5-8d8a-64fe840a9...@u10g2000prn.googlegroups.com>,
- - - A Balun It Ain't ! - But It Works :o)
- -
- - http://groups.google.com./group/rec.radio.shortwave/msg/5a334b2122c8ddbf
-
- This isn't hard to understand. This is a two part term, which refers
to
- the type of transformer. "BAL" refers to balanced and "UN" refers to
- unbalanced so the possibilities are BALBAL, UNUN, or BALUN.
-
- A long wire is unbalanced and a coax is unbalanced so the
transformer
- type you would use is a UNUN. If you had a dipole, which is balanced
- connected to a coax you would use a BALUN.
-
- --
- Telamon
- Ventura, California
-
Telamon - Good Explanation. - We Agree ! :o) ~ RHF
.