# Some practical values for a half-wave dipole antenna

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## Re: Some practical values for a half-wave dipole antenna

You are most welcome any time but if you have any specific idea as to the antenna you want then please come back. Ivan i8s especially good at antennas and I have some experience, not to mention all the other people here who are keen to help you.

BR Harry - SM0VPO

Nerja, Spain

BR Harry - SM0VPO

Nerja, Spain

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## Re: Some practical values for a half-wave dipole antenna

Thank you all for the information.

Regards.

Regards.

**Dyon**- Guest

## Re: Some practical values for a half-wave dipole antenna

__http://www.sm0vpo.com/antennas/anten.htm__- how antennas work

http://www.sm0vpo.com/antennas/dipole.htm - basic antenna

http://www.sm0vpo.com/antennas/vpole0.htm - quick with calculator

BR Harry

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*If success = A, then A = X + Y + Z, where X = work, Y = play and Z = keeping your mouth shut (Albert Einstein).*

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## Re: Some practical values for a half-wave dipole antenna

Dyon wrote:Hi Ivan,

I do not have any particular frequency in mind.

All I want is a complete info about a working half-dipole antenna (center-fed). The frequency does not matter much for my present purpose but it must be that antenna's fundamental and higher harmonics. I am interested to make some calculations.

The radiation pattern should be -if at all possible- the pattern for free space (away from ground) for the fundamental and some higher harmonics. The pattern must be measured, not calculated.

I will appreciate any help.

Thanks, Ionel

But the length of a half wave dipole will depend upon the frequency you wish it to be resonant at - it's like asking "How long is a piece of string".

The approximate length of a halfwave dipole (in feet) can be found from 468/MHz. That gives you the total length - obviously divide by two and feed the antenna at the centre point (quarter lambda up, quarter lambda down, assuming a vertical antenna). Impedance at the quarter wave feed point is 75R I believe.

See here for precise information: https://en.wikipedia.org/wiki/Dipole_antenna

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**DragonForce**- Posts : 85

Join date : 2012-11-25

Age : 56

Location : Bristol, SW UK

## Some practical values for a half-wave dipole antenna

Hi Ivan,

I do not have any particular frequency in mind.

All I want is a complete info about a working half-dipole antenna (center-fed). The frequency does not matter much for my present purpose but it must be that antenna's fundamental and higher harmonics. I am interested to make some calculations.

The radiation pattern should be -if at all possible- the pattern for free space (away from ground) for the fundamental and some higher harmonics. The pattern must be measured, not calculated.

I will appreciate any help.

Thanks, Ionel

I do not have any particular frequency in mind.

All I want is a complete info about a working half-dipole antenna (center-fed). The frequency does not matter much for my present purpose but it must be that antenna's fundamental and higher harmonics. I am interested to make some calculations.

The radiation pattern should be -if at all possible- the pattern for free space (away from ground) for the fundamental and some higher harmonics. The pattern must be measured, not calculated.

I will appreciate any help.

Thanks, Ionel

**Dyon**- Guest

## Re: Some practical values for a half-wave dipole antenna

Hi,

what band are you interested in ?

The voltage and current depend on the power in use (really much !! ). They are also affected by the surroundings - height above ground, nearby metallic objects etc.

Measuring of the radiation pattern is out of possibilities of an average ham on longer than decimeter waves. Probably a copter would be required ...

BR from Ivan

what band are you interested in ?

The voltage and current depend on the power in use (really much !! ). They are also affected by the surroundings - height above ground, nearby metallic objects etc.

Measuring of the radiation pattern is out of possibilities of an average ham on longer than decimeter waves. Probably a copter would be required ...

BR from Ivan

**Ivan**- Posts : 246

Join date : 2012-11-25

Location : Praha, Czechia

## Some practical values for a half-wave dipole antenna

Hi,

I would like to know the parameters of a real-life, working, tested, half-wavelength dipole antenna (center-fed).

I would appreciate if you could help me with information on:

- physical dimensions, length/diameter

- material used

- fundamental frequency (not theoretical, practical)

- amplitude of the voltage at the feeding point

- amplitude of the current

- measured radiation pattern

Many thanks, Ionel

I would like to know the parameters of a real-life, working, tested, half-wavelength dipole antenna (center-fed).

I would appreciate if you could help me with information on:

- physical dimensions, length/diameter

- material used

- fundamental frequency (not theoretical, practical)

- amplitude of the voltage at the feeding point

- amplitude of the current

- measured radiation pattern

Many thanks, Ionel

**Dyon**- Guest

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