RadioBanter - Baluns?

RadioBanter (https://www.radiobanter.com/)

- Antenna (https://www.radiobanter.com/antenna/)

- - Baluns? (https://www.radiobanter.com/antenna/136120-baluns.html)

JB wrote:

The Devil deceives many and jeers at the truth. But those who
call on the Lord in prayer keep him at bay. The sun shines on
the wicked and the righteous.

Your English is lacking. That second sentence is amusing to us
non-believers. Pray to your lord and you 'keep him at bay'.

These personal gods you just can't trust 'em!

--
M0WYM
www.radiowymsey.org

Sign today!
http://petitions.pm.gov.uk/SaveShortwave/

JB wrote:

It's would be pretty arrogant to consider that you have the ability to screw
up God's plan. We can't even be sure that Satan screwed up God's plan, but
it appears that there is some contention that is/was/does exist in the
heavenly realm.

Oh give us a break! It's pretty arrogant of you to assume that:

1) There is a god

2) That he has a plan

3) That there is such a beasty as satan

4) That there is a place called heaven

Still if it gets you through the night who I to deny you a walking
stick.

--
M0WYM
www.radiowymsey.org

Sign today!
http://petitions.pm.gov.uk/SaveShortwave/

JB wrote:
Salvation comes by invitation only.

There you go boys, just wait, lay back, smoke that joint, and wait
for the invite.

Goodbye self-determination - what a load of codswallop!

--
M0WYM
www.radiowymsey.org

Sign today!
http://petitions.pm.gov.uk/SaveShortwave/

M0WYM wrote:

...
Oh give us a break! It's pretty arrogant of you to assume that:

1) There is a god

2) That he has a plan

3) That there is such a beasty as satan

4) That there is a place called heaven

Still if it gets you through the night who I to deny you a walking stick.

Really? Interesting concept ... hydrogen just is, has always been,
always will be ... such as a belief in God?

So, no one made any of these elements, they "just happened?" Where is
your proof, what law is behind your logic. Doesn't the scientific
method demand proof in repeatable experiments? The experiment you imply
in your reference, I am ignorant of that one. I know you must be busy
revolving in that logical world you seem to be engrossed in--but, just
for my sake, you could you provide a reference to it so I can examine it
for myself?

Regards,
JS

--
It is like a nightmare where the public servants are the people which
the police are supposed to protect us from!

M0WYM wrote:
JB wrote:
Salvation comes by invitation only.

There you go boys, just wait, lay back, smoke that joint, and wait
for the invite.

Goodbye self-determination - what a load of codswallop!

What wasted verbiage, in response to wasted verbiage! My gawd man,
let's just toss some words back and forth ... yawn

Regards,
JS

--
It is like a nightmare where the public servants are the people which
the police are supposed to protect us from!

M0WYM wrote:

...
Your English is lacking. That second sentence is amusing to us
non-believers. Pray to your lord and you 'keep him at bay'.

These personal gods you just can't trust 'em!

If a personal attack fails to bring the victim to his knees:

1) Attempt an attack in the mans use of grammer.

2) Attempt an attack in the form of his writings.

3) Attempt an attack on the choice of the words (hell, just like
scrabble, longer/complex words should count for more! grin )

4) Attempt an attack on sentence structure, abbreviation, "slang", etc.

5) etc., etc. ...

Something will finally gain some idiots attention ...

Regards,
JS

--
It is like a nightmare where the public servants are the people which
the police are supposed to protect us from!

M0WYM wrote:
JB wrote:

It's would be pretty arrogant to consider that you have the ability to
screw
up God's plan. We can't even be sure that Satan screwed up God's
plan, but
it appears that there is some contention that is/was/does exist in the
heavenly realm.

OK. Since you seem to be "dirt stupid" and have been given some
ignorant, preconceived notions which you DO NOT have a mind capable of
lodging valid arguments to ... I will explain it to you, but just once:

You seem to think hydrogen is a "God"--is, always has been, always will
be ...

However, while you would discredit a GOD, you would have us believe
these elements which are, always have been and always will be, can, on
their own, "evolve" into complex beings (biological machines) such as
ourselves ...

However, in that same breath you will discredit that exactly such may
have occurred so long ago, in such a distant past we cannot even fathom,
and did result in a being so advanced, complex and so ahead of us that
we have no choice other than consider him/her/it/the-alien a God ...

Gees, your mind would have interested me--when I had engaged
kindergarten! ROFLOL

Regards,
JS

--
It is like a nightmare where the public servants are the people which
the police are supposed to protect us from!

On Sep 5, 7:23*am, Cecil Moore wrote:
wrote:
The ideal transmission line is common mode and does not radiate
because the fields cancel as you said earlier. The dipole antenna is
ALSO common mode but the fileds do NOT cancel because the conductors
are physically 180 degrees apart from each other so they cannot
interfere with each other; instead the fields radiate into free space
rather than cancel each other out.

If transmission line currents were common-mode, they would radiate
like crazy and would be an antenna instead of a transmission line.
When one shorts the two wires together and feeds the system Marconi
style against ground, then the currents are common-mode. (Please
switch your news-reader to fixed font). A '+' indicates a connection,
not polarity.

* +--------------------
* | * current reference
(V)
* | * Differential currents to antenna
* +--------------------
* * * Normal Transmission Line mode designed not to radiate

* +----+------------------
* | * * | *current reference
(V) * *|
* | * * | *Common-mode currents (becomes antenna)
* | * * +------------------
GND * * * Marconi Style feed designed to radiate

If the
currents on a transmission line are differential, how would (COULD)
they be converted to common mode currents on the antenna? We would
need a 180 degree phase shift somewhere.

I'm glad you asked. When we take the last 1/4WL of transmission
line and open it up into a dipole, we have rotated one wire by
-90 degrees and the other wire by +90 degrees. That's a 180 degree
difference. The transmission line currents are 180 degrees out of
phase. The extra 180 degrees of physical rotation subtracts from
the 180 degrees in the transmission line for a total of zero
degrees (in phase) at the antenna feedpoint. This is explained
in detail in "Antenna Theory", by Balanis, 2nd edition, page 18.
I will try to duplicate it here using fixed font ASCII graphics.

* * * * * * * * In Phase Antenna Currents
--------------------+ *+--------------------
* * * * * * * * * * * * *| *|
* * * * * * * * * * * * *| *|
* +------------------+ *|
(V) * * Differential * * * |
* +--------------------+
* Transmission Line Currents

Note the out of phase currents in the transmission line results
in in-phase currents in the dipole antenna.
--
73, Cecil *http://www.w5dxp.com

Upon doing independent research, it turns out my theory is exactly the
same as your's but my terminology was reversed. The situation is
summed up in an article by W8ji:

(quote)...the line will not radiate or contain substantial electric or
magnetic fields external to the line area. The lack of external
fields, even at a very small distances, is rooted in two conditions:

1.) All outgoing currents on one conductor are matched by equal
level and exactly opposite phase currents on a return conductor at any
given point along the line. (The reason I said the line will not
radiate) This causes an exactly equal and opposite magnetic field
along each conductor. The opposing magnetic fields caused by equal
currents flowing opposite directions cancel magnetic fields outside
the general area of the two conductors.

2.) All voltages from each conductor of the line to the outside
environment surrounding the line are either contained within a closed
shield, or are exactly equal and opposite an imaginary neutral
reference point representing the environment around the line (balanced
lines) (I discussed this imaginary reference point in some detail as
well). We always have a constant ****differential*** voltage across
the line (between the conductors) and that voltage changes only with
standing wave ratio as we move along the line.

3.) The vector product of differential current flowing in
conductors and voltage between line conductors at any point along the
line always equals the power transmitted in transmission line mode.
(unquote)

So I simply reversed the terminology and I agree that your use of the
term "differential" was correct. I was calling the mirror image
current pattern "common mode" when it should be differential.

But I still shy away from matching impedances with a "choke". I would
match impedances with a balun or RF transformer. I agree that you
must isolate, either mechancially or electrically, the input from
output on a balun. I made the simple mistake of confusing the terms
differential and common mode. Thank you for the correction. And I have
tried using the CM mode marconi style feed (shorting the antenna at
the transceiver input terminals) to try to get my 80m G5RV to radiate
at 2Mhz some years ago, as suggested by MFJ in their instruction
manual, to no avail. I am sure it can radiate quite well at some
frequency however!

"Michael Coslo" wrote in message
...

snip

For me, a person is allowed to believe whatever they want, as long as it
doesn't affect me. Unfortunately, too many of them don't get that part
and want to force themselves on everyone.

Oddly enough, the greatest sermon, direct orders from the man himself is
ignored by these folk.

That would be .... the "Do unto others ... " if I get your drift.

Proselytizing has its place I suppose, but I wish they'd figure out that I'm
not interested and quit ringing my doorbell ... them and AT&T.