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Old June 19th 06, 04:33 PM posted to rec.radio.amateur.antenna
BILL GRIESCH -K2WDG
 
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Default i want to know the length of a 6m dipole

wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh
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Old June 19th 06, 05:52 PM posted to rec.radio.amateur.antenna
F8BOE
 
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Default i want to know the length of a 6m dipole

physical or electrical?

With such a question I'm wondering what "technician licence class" means...
BTW looking at your mail address, I think I'll rather send anything via
eqsl.

Or perhaps did I miss something? My English is not really perfect.

Keep on trying.


BILL GRIESCH -K2WDG trolled:

wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh


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Old June 19th 06, 06:30 PM posted to rec.radio.amateur.antenna
gravity
 
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Default i want to know the length of a 6m dipole


"BILL GRIESCH -K2WDG" wrote in message
...
wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh


the general rule is L = 234/F, where F is the frequency in megahertz, and L
is the length of a quarter wave element in feet.

this is a strange troll, can't you come up with something better?

Gravity


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Old June 19th 06, 06:55 PM posted to rec.radio.amateur.antenna
Dave
 
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Default i want to know the length of a 6m dipole

3 meters.

Almost 10 years licensed ... WOW

BILL GRIESCH -K2WDG wrote:
wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh


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Old June 19th 06, 09:12 PM posted to rec.radio.amateur.antenna
Brian Howie
 
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Default i want to know the length of a 6m dipole

In message , BILL GRIESCH -K2WDG
writes
wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full
blowen ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh


By chance I made one at the weekend. 113.5", 1/2 " diam ali tubing. I
used the yoke of an old TV CRT as a choke balun with a few turns of
UR67.

If you don't have space, a simple cubical quad is pretty compact.

73 Brian GM4DIJ
--
Brian Howie


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Old June 20th 06, 01:35 AM posted to rec.radio.amateur.antenna
Butch Magee
 
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Default i want to know the length of a 6m dipole

gravity wrote:
"BILL GRIESCH -K2WDG" wrote in message
...

wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh



the general rule is L = 234/F, where F is the frequency in megahertz, and L
is the length of a quarter wave element in feet.

this is a strange troll, can't you come up with something better?

Gravity


The formula, which I learned as a novice, I think, is length is=468/f(in
mHz)
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Old June 20th 06, 02:10 AM posted to rec.radio.amateur.antenna
WB2YIP
 
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Default i want to know the length of a 6m dipole


BILL GRIESCH -K2WDG wrote:
wondering if someone can provide me with the length or the plans of a
6m dipole.. i have 6m's but i dont have the room to put up a full blowen
ant i think that a dipole would work fo me

please email at k2wdg@k2wdg with any information

thanks in advance

bill k2wdgh


Boy, that's a tough question! Wonder why you bothered to post - would
think a ham could calculate that one - additionally, its so simple to
calculate or to find the length on the Internet these days, probably
took you longer to type the question...boy, makes ya wonder...remember
when?

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Old June 20th 06, 07:10 AM posted to rec.radio.amateur.antenna
Buck
 
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Default i want to know the length of a 6m dipole

On Mon, 19 Jun 2006 19:35:37 -0500, Butch Magee
wrote:

gravity wrote:


the general rule is L = 234/F, where F is the frequency in megahertz, and L
is the length of a quarter wave element in feet.

this is a strange troll, can't you come up with something better?

Gravity


The formula, which I learned as a novice, I think, is length is=468/f(in
mHz)



Read the text carefully, he is talking about each of the two 1/4 wave
elements that make up a half wave dipole.

BTW, what is 468/2 ???
--
73 for now
Buck
N4PGW
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Old June 26th 06, 01:43 PM posted to rec.radio.amateur.antenna
Reg Edwards
 
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Default i want to know the length of a 6m dipole

There's too much fuss made about resonant length of simple wire
antennas.

(1) Radiating efficiency is hardly affected by being as much as 20 or
30 percent off-resonance in terms of antenna length.

(2) The feedpoint resistance at resonance may indeed provide the
theoretical correct termination for the transmission line for 1-to-1
SWR in the middle of an amateur band. But it is way off resonance at
the band edges with an SWR which causes little if any concern.

(3) The impedance of the transmission line is usually known only
approximately. The reactance of Zo is always ignored. So exact SWR on
the line is never known. SWR varies slowly with small changes in
antenna off-resonance length.

(4) If an antenna tuner can accommodate changes in input impedance
from one band to another it can certainly accommodate the omission of
the correction factor 468/F.

(5) So it hardly matters whether the correction is applied or not. The
minute difference in operating performance will be detected only by an
impossible A/B test. You can put away your pruning shears.

The theoretical resonant length of a 1/2-wave dipole is 150/F metres.
The actual resonant length is very slightly shorter.

In free space, the shortening depends on length-to-diameter ratio of
the antenna conductor. But at low heights above ground the shortening
effect increases.

When the antenna wire is lying on the ground its velocity factor is
approximately 1/2 of the free space value of 1.

So you see the formula 468/F, although good enough for most purposes
if you want to use it, is very approximate.

The question is about the resonant length of a 6m dipole.

Is the dipole 6 metres long or is it resonant in the 6 metre amateur
band? Questioners should make themselves clear.

Assuming it is 50 MHz, resonant dipole length is very nearly 150/F
metres = 3 metres.

But the answer depends on conductor diameter. If frequency is 50 MHz
and the antenna is constructed with 14 gauge wire then the resonant
dipole length is 97 percent of 3 metres.

If the anenna is constructed of 1", 25mm, diameter tubes, then the
resonant length is a little shorter. It is 94 percent of 3 metres.

But actual lengths are non-critical. You can use a tape measure or a
wooden ruler. And don't worry if you can't find your spectacles.
----
Reg.


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Old June 27th 06, 12:55 AM posted to rec.radio.amateur.antenna
John - KD5YI
 
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Default i want to know the length of a 6m dipole

Reg Edwards wrote:
There's too much fuss made about resonant length of simple wire
antennas.

(1) Radiating efficiency is hardly affected by being as much as 20 or
30 percent off-resonance in terms of antenna length.

(2) The feedpoint resistance at resonance may indeed provide the
theoretical correct termination for the transmission line for 1-to-1
SWR in the middle of an amateur band. But it is way off resonance at
the band edges with an SWR which causes little if any concern.

(3) The impedance of the transmission line is usually known only
approximately. The reactance of Zo is always ignored. So exact SWR on
the line is never known. SWR varies slowly with small changes in
antenna off-resonance length.

(4) If an antenna tuner can accommodate changes in input impedance
from one band to another it can certainly accommodate the omission of
the correction factor 468/F.

(5) So it hardly matters whether the correction is applied or not. The
minute difference in operating performance will be detected only by an
impossible A/B test. You can put away your pruning shears.

The theoretical resonant length of a 1/2-wave dipole is 150/F metres.
The actual resonant length is very slightly shorter.

In free space, the shortening depends on length-to-diameter ratio of
the antenna conductor. But at low heights above ground the shortening
effect increases.

When the antenna wire is lying on the ground its velocity factor is
approximately 1/2 of the free space value of 1.

So you see the formula 468/F, although good enough for most purposes
if you want to use it, is very approximate.

The question is about the resonant length of a 6m dipole.

Is the dipole 6 metres long or is it resonant in the 6 metre amateur
band? Questioners should make themselves clear.

Assuming it is 50 MHz, resonant dipole length is very nearly 150/F
metres = 3 metres.

But the answer depends on conductor diameter. If frequency is 50 MHz
and the antenna is constructed with 14 gauge wire then the resonant
dipole length is 97 percent of 3 metres.

If the anenna is constructed of 1", 25mm, diameter tubes, then the
resonant length is a little shorter. It is 94 percent of 3 metres.

But actual lengths are non-critical. You can use a tape measure or a
wooden ruler. And don't worry if you can't find your spectacles.
----
Reg.



Hook, line, and sinker!
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