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Balun suggestions

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Jim Allen

Balun suggestions

K2/100 and KAT100 here.

I am changing around my modest antenna configuration now. I have been using the K2/100 with my AH-4, and now wish to use the KAT100 with balanced feedline antennas.

What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW.

73 de W6OGC Jim Allen

Sent from my iPad
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WA2SI

Re: Balun suggestions

I have to firmly vouch for Balun Concepts.

Sent from my android device.

-----Original Message-----
From: Jim Allen <[hidden email]>
To: [hidden email]
Sent: Thu, 04 Feb 2016 15:55
Subject: [Elecraft] Balun suggestions

K2/100 and KAT100 here.

I am changing around my modest antenna configuration now. I have been using the K2/100 with my AH-4, and now wish to use the KAT100 with balanced feedline antennas.

What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW.

73 de W6OGC Jim Allen

Sent from my iPad
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Elecraft mailing list

Re: Balun suggestions

In reply to this post by Jim Allen

Don't by-pass the Elecraft BL-2 $40 250 W 4:1 and 1:1 select able .
Mel, K6KBE

From: Walter Underwood <[hidden email]>
To: Elecraft Reflector <[hidden email]>
Sent: Thursday, February 4, 2016 1:17 PM
Subject: Re: [Elecraft] Balun suggestions

Balun Designs makes high quality baluns at fair prices.

http://www.balundesigns.com/ <http://www.balundesigns.com/>

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

> On Feb 4, 2016, at 1:11 PM, Bert Craig <[hidden email]> wrote:
>
> I have to firmly vouch for Balun Concepts.
>
> Sent from my android device.
>
> -----Original Message-----
> From: Jim Allen <[hidden email]>
> To: [hidden email]
> Sent: Thu, 04 Feb 2016 15:55
> Subject: [Elecraft] Balun suggestions
>
> K2/100 and KAT100 here.
>
> I am changing around my modest antenna configuration now. I have been using the K2/100 with my AH-4, and now wish to use the KAT100 with balanced feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW.
>
> 73 de W6OGC Jim Allen
>
> Sent from my iPad
> ______________________________________________________________
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Re: Balun suggestions

In reply to this post by Jim Allen

blockquote, div.yahoo_quoted { margin-left: 0 !important; border-left:1px #715FFA solid !important; padding-left:1ex !important; background-color:white !important; } Bob Rumsey, KZ5R of Balun Designs makes exceptional products & is always responsive if you have a question. I use several of his baluns.
David RutledgeAL5M

Sent from Yahoo Mail for iPhone

On Thursday, February 4, 2016, 15:17, Walter Underwood <[hidden email]> wrote:

Balun Designs makes high quality baluns at fair prices.

http://www.balundesigns.com/ <http://www.balundesigns.com/>

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

Don Wilhelm-4

Re: Balun suggestions

In reply to this post by Jim Allen

Jim,

If your balanced feedline comes into the shack and you are running QRP,
take a look at the Elecraft BL2.

73,
Don W3FPR

On 2/4/2016 3:55 PM, Jim Allen wrote:

> K2/100 and KAT100 here.
>
> I am changing around my modest antenna configuration now. I have been using the K2/100 with my AH-4, and now wish to use the KAT100 with balanced feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW.
>
> 73 de W6OGC Jim Allen
>
> Sent from my iPad
> ______________________________________________________________
> Elecraft mailing list
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Bob McGraw - K4TAX

Re: Balun suggestions

In reply to this post by Jim Allen

As one that has personally used a balanced fed antennas for years, I
suggest you review the info on this site.
http://www.dj0ip.de/balun-stuff/ <http://www.dj0ip.de/balun-stuff/>

Good stuff on evaluating or building a proper balun.

And for open wire fed antennas:
http://www.dj0ip.de/open-wire-fed-ant/

To answer your question, a high power 1:1 current balun is likely best.
Of course you could built a balanced tuner as I did. Problem solved.
That's another story.

Keep in mind that balun power ratings are for "matched" conditions.
Which in fact is never the case with a center fed wire and open wire or
a balanced feed line. At a mighty 5 watts it would not be of concern.

If at all possible, run the balanced feed line from the antenna feed
point all the way to the operating position. Keep the coax run between
the tuner output and balun input as short as practical. After all, the
reason to use balanced feed line is to take advantage of the low loss
properties.

Never fear, the use of balanced feed line is not near as critical or
fussy as the "masses" will so tout. Many hams express fear in using
balanced feed systems, largely because of what they have heard. Mostly
because it frankly isn't fact. Mine feeds a 256 ft center fed wire and
comes down the tower supported on home made 9" PVC stand-offs, through
the attic eve vent, across the roof rafters, and drops down through the
ceiling to the tuner on the shelf above the desk. Not bad for a 160M -
10M antenna. {see my pix on QRZ.COM that shows a bit of the line
going up the wall.}

73
Bob, K4TAX

<http://www.dj0ip.de/open-wire-fed-ant/>

On 2/4/2016 2:55 PM, Jim Allen wrote:

Wes (N7WS)

Re: Balun suggestions

In reply to this post by Jim Allen

I just pinched myself; I'm not dreaming and it's not April 1st, so I guess
you're serious.

You are also so wrong on so many points, I'm not going to waste time trying to
refute or correct them.

Jim, please ignore everything said below.

Wes N7WS

On 2/4/2016 3:05 PM, Ron D'Eau Claire wrote:

> Your feed line will do the job by itself so no additional "balun" is needed.
> Keep in mind that a 1:1 balun is really just a length of feed line, usually
> wound on a toroidal core to make the required length shorter than if it was
> in open air. The "old-school" baluns were just a pair of air wound coils.
>
> If your balanced feed line is at least 1/4 wavelength long, the currents
> will be "balanced" (equal and out of phase) at the antenna. That assumes
> your antenna is perfectly balanced to provide a perfectly balanced load,
> which "balanced" antennas almost never do. There are just too many
> variables. So expect excellent results even with shorter feed lines. The
> amount of radiation (or pickup) from the feed line even at the rig end is
> small in any case.
>
> Connect one side of the open wire feed line to the KAT100 SO-239 center pin
> and the other to the KAT100 ground terminal.
>
> 73, Ron AC7AC
>
>
>
> -----Original Message-----
> K2/100 and KAT100 here.
>
> I am changing around my modest antenna configuration now. I have been using
> the K2/100 with my AH-4, and now wish to use the KAT100 with balanced
> feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost always
> run 5 watts, all CW.
>
> 73 de W6OGC Jim Allen
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]
>

Jim Brown-10

Re: Balun suggestions

In reply to this post by Jim Allen

On Thu,2/4/2016 12:55 PM, Jim Allen wrote:
> What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW.

k9yc.com/RFI-Ham.pdf Since you're running QRP, a single 2.4-in o.d. #31
core is all you need. Study the data in Appendix One for small diameter
wire, and wind the number of turns of your coax through it that puts the
impedance peak in the frequency range where you want to operate.

73, Jim K9YC
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Don Wilhelm-4

Re: Balun suggestions

In reply to this post by Wes (N7WS)

Wes,

I don't mean to be contentious, but under ideal conditions, what Ron
said is true. Even though we often refer to the output of the KAT500
(or any other device that normally connects to a coaxial line, the
currents on the output should be equal and opposite - which is the
definition of balanced.
Consider the currents between the center conductor and the inside of the
shield for coax. They must be equal and opposite. It is the common
mode current on the outside of the feedline that produces any unbalance.

So connecting a balanced feedline to a PL-259 is not so far fetched -
providing the shell of the PL-259 (and enclosure of the KAT500) is not
grounded. If you have decided to ground your KAT500, then you would
need to use a balun - so "it all depends". Be aware of "sneak grounds".

73,
Don W3FPR

On 2/4/2016 7:17 PM, Wes (N7WS) wrote:

> I just pinched myself; I'm not dreaming and it's not April 1st, so I
> guess you're serious.
>
> You are also so wrong on so many points, I'm not going to waste time
> trying to refute or correct them.
>
> Jim, please ignore everything said below.
>
> Wes N7WS
>
>
>
> On 2/4/2016 3:05 PM, Ron D'Eau Claire wrote:
>> Your feed line will do the job by itself so no additional "balun" is
>> needed.
>> Keep in mind that a 1:1 balun is really just a length of feed line,
>> usually
>> wound on a toroidal core to make the required length shorter than if
>> it was
>> in open air. The "old-school" baluns were just a pair of air wound
>> coils.
>>
>> If your balanced feed line is at least 1/4 wavelength long, the currents
>> will be "balanced" (equal and out of phase) at the antenna. That assumes
>> your antenna is perfectly balanced to provide a perfectly balanced load,
>> which "balanced" antennas almost never do. There are just too many
>> variables. So expect excellent results even with shorter feed lines. The
>> amount of radiation (or pickup) from the feed line even at the rig
>> end is
>> small in any case.
>>
>> Connect one side of the open wire feed line to the KAT100 SO-239
>> center pin
>> and the other to the KAT100 ground terminal.
>>
>> 73, Ron AC7AC
>>
>>
>>
>> -----Original Message-----
>> K2/100 and KAT100 here.
>>
>> I am changing around my modest antenna configuration now. I have
>> been using
>> the K2/100 with my AH-4, and now wish to use the KAT100 with balanced
>> feedline antennas.
>>
>> What balun, homebrew or commercial, if any, should I use? I almost
>> always
>> run 5 watts, all CW.
>>
>> 73 de W6OGC Jim Allen
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
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>

Jim Miller

Re: Balun suggestions

I suggest reading work by w9cf before getting concerned about balancing tuners.

http://fermi.la.asu.edu/w9cf/articles/balun/index.html

On Feb 4, 2016, at 7:38 PM, Don Wilhelm <[hidden email]> wrote:

Wes,

I don't mean to be contentious, but under ideal conditions, what Ron said is true. Even though we often refer to the output of the KAT500 (or any other device that normally connects to a coaxial line, the currents on the output should be equal and opposite - which is the definition of balanced.
Consider the currents between the center conductor and the inside of the shield for coax. They must be equal and opposite. It is the common mode current on the outside of the feedline that produces any unbalance.

So connecting a balanced feedline to a PL-259 is not so far fetched - providing the shell of the PL-259 (and enclosure of the KAT500) is not grounded. If you have decided to ground your KAT500, then you would need to use a balun - so "it all depends". Be aware of "sneak grounds".

73,
Don W3FPR

> On 2/4/2016 7:17 PM, Wes (N7WS) wrote:
> I just pinched myself; I'm not dreaming and it's not April 1st, so I guess you're serious.
>
> You are also so wrong on so many points, I'm not going to waste time trying to refute or correct them.
>
> Jim, please ignore everything said below.
>
> Wes N7WS
>
>
>
>> On 2/4/2016 3:05 PM, Ron D'Eau Claire wrote:
>> Your feed line will do the job by itself so no additional "balun" is needed.
>> Keep in mind that a 1:1 balun is really just a length of feed line, usually
>> wound on a toroidal core to make the required length shorter than if it was
>> in open air. The "old-school" baluns were just a pair of air wound coils.
>>
>> If your balanced feed line is at least 1/4 wavelength long, the currents
>> will be "balanced" (equal and out of phase) at the antenna. That assumes
>> your antenna is perfectly balanced to provide a perfectly balanced load,
>> which "balanced" antennas almost never do. There are just too many
>> variables. So expect excellent results even with shorter feed lines. The
>> amount of radiation (or pickup) from the feed line even at the rig end is
>> small in any case.
>>
>> Connect one side of the open wire feed line to the KAT100 SO-239 center pin
>> and the other to the KAT100 ground terminal.
>>
>> 73, Ron AC7AC
>>
>>
>>
>> -----Original Message-----
>> K2/100 and KAT100 here.
>>
>> I am changing around my modest antenna configuration now. I have been using
>> the K2/100 with my AH-4, and now wish to use the KAT100 with balanced
>> feedline antennas.
>>
>> What balun, homebrew or commercial, if any, should I use? I almost always
>> run 5 watts, all CW.
>>
>> 73 de W6OGC Jim Allen
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
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>
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> Please help support this email list: http://www.qsl.net/donate.html
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Wes (N7WS)

Re: Balun suggestions

In reply to this post by Don Wilhelm-4

I was wrong. Clearly, I'm dreaming.

On 2/4/2016 5:38 PM, Don Wilhelm wrote:

> Wes,
>
> I don't mean to be contentious, but under ideal conditions, what Ron said is
> true. Even though we often refer to the output of the KAT500 (or any other
> device that normally connects to a coaxial line, the currents on the output
> should be equal and opposite - which is the definition of balanced.
> Consider the currents between the center conductor and the inside of the
> shield for coax. They must be equal and opposite. It is the common mode
> current on the outside of the feedline that produces any unbalance.
>
> So connecting a balanced feedline to a PL-259 is not so far fetched -
> providing the shell of the PL-259 (and enclosure of the KAT500) is not
> grounded. If you have decided to ground your KAT500, then you would need to
> use a balun - so "it all depends". Be aware of "sneak grounds".
>
> 73,
> Don W3FPR
>
> On 2/4/2016 7:17 PM, Wes (N7WS) wrote:
>> I just pinched myself; I'm not dreaming and it's not April 1st, so I guess
>> you're serious.
>>
>> You are also so wrong on so many points, I'm not going to waste time trying
>> to refute or correct them.
>>
>> Jim, please ignore everything said below.
>>
>> Wes N7WS
>>

Jim Brown-10

Re: Balun suggestions

In reply to this post by Jim Allen

On Thu,2/4/2016 12:55 PM, Jim Allen wrote:
> I am changing around my modest antenna configuration now. I have been using the K2/100 with my AH-4, and now wish to use the KAT100 with balanced feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost always run 5 watts, all CW

You didn't say what your antenna is or what bands you want to work.
Antennas, feedlines, and tuners are a SYSTEM, and must be considered as
a system. Why do you want to use "balanced" line? Has someone told you
it's lower loss, and you can use any random wire (or some "magic" length
of wire on all bands?

Are you trying to use a non-resonant antenna on multiple bands? If so,
why? Is that the only sort of antenna you can hang? There are serious
issues with this sort of antenna. First, there can be significant
feedline losses. Second, these antennas are nearly impossible to choke
to kill common mode noise, so they can be noisy. Off-center-fed antennas
are unbalanced by their nature, so they're inherently noisy. Even a
center-fed antenna will be unbalanced by its surroundings -- sloping
ground, variable height, proximity to other conductors on one end but
not the other, etc.

Take a look at the antenna planning tutorials on my website. All of the
options shown there are superior to most "all-band" wires.

73, Jim K9YC

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Wes (N7WS)

Re: Balun suggestions

In reply to this post by Don Wilhelm-4

You mean like that "sneak ground" from the input of the tuner back to the
grounded amp or exciter? Or are they floating too?

On 2/4/2016 5:38 PM, Don Wilhelm wrote:
>
> So connecting a balanced feedline to a PL-259 is not so far fetched -
> providing the shell of the PL-259 (and enclosure of the KAT500) is not
> grounded. If you have decided to ground your KAT500, then you would need to
> use a balun - so "it all depends". Be aware of "sneak grounds".
>
> 73,
> Don W3FPR
>

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Don Wilhelm-4

Re: Balun suggestions

Wes and all,

Yes, that is one source of "sneak ground". A balun will cure that
condition.

73,
Don W3FPR

On 2/4/2016 11:48 PM, Wes (N7WS) wrote:

> You mean like that "sneak ground" from the input of the tuner back to
> the grounded amp or exciter? Or are they floating too?
>
> On 2/4/2016 5:38 PM, Don Wilhelm wrote:
>>
>> So connecting a balanced feedline to a PL-259 is not so far fetched -
>> providing the shell of the PL-259 (and enclosure of the KAT500) is
>> not grounded. If you have decided to ground your KAT500, then you
>> would need to use a balun - so "it all depends". Be aware of "sneak
>> grounds".
>>

Jim Brown-10

Re: Balun suggestions

In reply to this post by Wes (N7WS)

On Thu,2/4/2016 5:35 PM, Wes (N7WS) wrote:
> Even though we often refer to the output of the KAT500 (or any other
> device that normally connects to a coaxial line, the currents on the
> output should be equal and opposite - which is the definition of
> balanced.

Sorry, that is NOT the definition of "balance." Balance is defined by
equal potential to the reference plane, which for most land-based
antennas is either the earth or the chassis of the transmitter that
feeds it, which is usually ground referenced.

> Consider the currents between the center conductor and the inside of
> the shield for coax. They must be equal and opposite. It is the
> common mode current on the outside of the feedline that produces any
> unbalance.

No, the common mode current is the RESULT of imbalance. AND -- common
mode current is present in two-wire feedlines when the antenna or the
transmitter is unbalanced. In those 2-wire feedlines, common mode
current is the DIFFERENCE between the current in the two conductors.

Note also that feedlines have wavelength, and both voltage and current
vary along the line. The DIFFERENTIAL voltage and current vary as a
function of the behavior of the line as a transmission line, with Vf
being that of the line. The COMMON MODE voltage and current vary along
the line as a function of the line's behavior as an ANTENNA, where Vf is
determined by the insulation on the outer conductor(s), so is 0.98 - 0.99.

I laugh at those who attempt to measure current in both sides of a
2-wire line and think that what they have measured is the current at
every point on the line. It is not -- it's only the current at the point
you measured it, and it's only right there if your measurement technique
is without error. Which ain't easy.

73, Jim K9YC
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Vic Rosenthal

Re: Balun suggestions

In reply to this post by Jim Allen

Jim,

You might find that on some bands your antenna tunes better with a 1:1
balun and on others with a 4:1. Therefore, I recommend the Elecraft
balun, which is switchable. It's rated at 250w so it should be adequate.

73,
Vic, 4X6GP/K2VCO
Rehovot, Israel
http://www.qsl.net/k2vco/

On 4 Feb 2016 22:55, Jim Allen wrote:

> K2/100 and KAT100 here.
>
> I am changing around my modest antenna configuration now. I have
> been using the K2/100 with my AH-4, and now wish to use the KAT100
> with balanced feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost
> always run 5 watts, all CW.
>
> 73 de W6OGC Jim Allen
>
> Sent from my iPad

gm3sek

Re: Balun suggestions

In reply to this post by Wes (N7WS)

Wes's point is that twin feeder is not automatically "balanced" - very far
from it! Twin feeder happily supports both differential (equal and opposite,
balanced) currents and common-mode current at the same time.

So, in the real world, there is no such thing as "balanced" feedline unless
YOU actually DID something to FORCE it to be balanced. And the way to do
that is to insert a common-mode choke that enforces equal-and-opposite
currents at that particular location... though even then, it can do nothing
to prevent the regrowth of common-mode current elsewhere along the line.

73 from Ian GM3SEK

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Wes
(N7WS)
Sent: 05 February 2016 00:18
To: [hidden email]
Subject: Re: [Elecraft] Balun suggestions

I just pinched myself; I'm not dreaming and it's not April 1st, so I guess
you're serious.

You are also so wrong on so many points, I'm not going to waste time trying
to refute or correct them.

Jim, please ignore everything said below.

Wes N7WS

On 2/4/2016 3:05 PM, Ron D'Eau Claire wrote:
> Your feed line will do the job by itself so no additional "balun" is
needed.
> Keep in mind that a 1:1 balun is really just a length of feed line,
> usually wound on a toroidal core to make the required length shorter
> than if it was in open air. The "old-school" baluns were just a pair of
air wound coils.

>
> If your balanced feed line is at least 1/4 wavelength long, the
> currents will be "balanced" (equal and out of phase) at the antenna.
> That assumes your antenna is perfectly balanced to provide a perfectly
> balanced load, which "balanced" antennas almost never do. There are
> just too many variables. So expect excellent results even with shorter
> feed lines. The amount of radiation (or pickup) from the feed line
> even at the rig end is small in any case.
>
> Connect one side of the open wire feed line to the KAT100 SO-239
> center pin and the other to the KAT100 ground terminal.
>
> 73, Ron AC7AC
>
>
>
> -----Original Message-----
> K2/100 and KAT100 here.
>
> I am changing around my modest antenna configuration now. I have been
> using the K2/100 with my AH-4, and now wish to use the KAT100 with
> balanced feedline antennas.
>
> What balun, homebrew or commercial, if any, should I use? I almost
> always run 5 watts, all CW.
>
> 73 de W6OGC Jim Allen
>
>
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w7aqk

Re: Balun suggestions

In reply to this post by Jim Allen

Jim B. and All,

I don't know what the precise definition for "balanced" will end up being
(assuming we end up with a consensus), but In Jim B's critique about what
was said, I think he cut and pasted so as to erroneously attribute comments
made by Don, W3FPR, as being made by Wes N7WS. It's getting hard to keep
track of who said what! Hi. Interesting debate, however.

Dave W7AQK

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Wes (N7WS)

Re: Balun suggestions

Correct on all points.

On 2/5/2016 6:06 AM, w7aqk wrote:

> Jim B. and All,
>
> I don't know what the precise definition for "balanced" will end up being
> (assuming we end up with a consensus), but In Jim B's critique about what was
> said, I think he cut and pasted so as to erroneously attribute comments made
> by Don, W3FPR, as being made by Wes N7WS. It's getting hard to keep track of
> who said what! Hi. Interesting debate, however.
>
> Dave W7AQK
>

Jim Brown-10

Re: Balun suggestions

In reply to this post by w7aqk

On Fri,2/5/2016 5:06 AM, w7aqk wrote:
> I don't know what the precise definition for "balanced" will end up
> being (assuming we end up with a consensus),

The laws of physics are not determined by consensus. I am citing the
definition upon which IEC and AES Standards are based, which are
established by international bodies of first rate engineers. I'm a
member of the AES Standards Committee. It may come as a shock to some,
but almost everything fundamental about electricity, electronics, audio,
radio, and transmission lines was well understood and documented nearly
100 years ago, and much of it decades earlier.

There's a slide presentation on RFI on my website that addresses the
topic of balance. GM3SEK and N7WS clearly understand it.

73, Jim K9YC
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