HF multiband beam "MARÍA MALUCA"

Carlos Fonseca - CT1GFQ

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Dec 19, 2012, 2:19:32 PM12/19/12

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HF multiband beam "MARÍA MALUCA"

Published as an article on URE's magazine "Radioaficionados" on January 2009

Invented by José Salvador Luiz Victor Marinaro (PY2BBP) in 1957, this antenna is more than a dipole, it is a dipole with a passive element which works as a director or reflector element so there is a directional gain. Works from 20 to 6 meter bands. In 12, 10 and 6 meter the passive element works as reflector instead of director, then a 180º rotation is needed to work the same direction.

To build the elements can be used aluminium pipes of several diameters, linked and fixed by screws, to get the needed lengths. The dipole stands its two parts by a pvc pipe and a methacrylate plate.

To feed this antenna a 450Ω ladder line is needed and antenna tuner too. Also a BALUN is needed which can be 1:1 or 4:1. Mine is a 1:1 current BALUN wound on a FT-240-43 core (12 bifilar turns).

Ladder line length is important because according to the length you cut it and frequency, impedance values can be so high than the tuner cannot match. Minimum length is about 13.7 meters. Then I added a RG-213 to reach my radio room. This length must be also adjusted to be matched by the tuner with SWR 1:1. The following diagram shows the instalation.

The ladder line must be insulated from metalic objects about 15 to 20 cm. Can be replaced by two parallel RG-62 (93Ω) coaxial cables, then feed line will be 186Ω.

Map shows contacts I made when testing the antenna "Maria Maluca". In black color are 20 meter band QSOs, blue are on 17m. and red are on 15m. Mode was BPSK31 in all contacts, power 30-40W. The 80% of QSOs reported RST 599.

Technical data:

Bands: 20, 17, 15, 12, 10 y 6 meter

Gain: 7.26 - 2.25dBi

Front/Back relation (F/B): 6.63 - 0.48dB

Bandwidth @ SWR 2:1: 20m.: 135kHz

17m.: >100kHz

15m.: 260kHz

12m.: >100kHz

10m.: 390kHz

Max power: 1000W

Boom length: 1.46 m.

Longest element: 7.56 m.

Turning radius: 3.9 m.

Windload: 0.2 m²

Weight: 3.6 kg

http://perso.orange.es/isaac.dg/antena%20maria%20maluca.htm

73's de Carlos CT1GFQ
SKCC#466
REP#1406

Filipe Lopes

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Dec 20, 2012, 6:31:23 AM12/20/12

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Já alguem testou esta antena ?

F. Lopes CT1ILT

2012/12/19 Carlos Fonseca - CT1GFQ <ct1gfq...@gmail.com>

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Regards,
Filipe Lopes
CT1ILT aka CR6K

Joel Lobão

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Dec 20, 2012, 6:36:51 AM12/20/12

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O ganho é que não me parece muito real... Mas pronto.

Joel - CT1HXB

ct1dmk

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Dec 20, 2012, 4:10:19 PM12/20/12

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Sim, foi super usada no final nos anos 70 e algo nos anos 80.
Vários colegas seguramente se lembram de quando se falava imenso desta
antena.
mas eu não experimentei, apenas me lembro de ser algo
que todos diziam maravilhas naquela época.
Mas... não sei mais do que isto.

lc
ct1dmk.

On 12/20/2012 11:31 AM, Filipe Lopes wrote:
> Já alguem testou esta antena ?
>
> F. Lopes CT1ILT
>
>
>
> 2012/12/19 Carlos Fonseca - CT1GFQ <ct1gfq...@gmail.com

> <mailto:ct1gfq...@gmail.com>>
>
> /HF multiband beam "MARÍA MALUCA"/
>
> /*Published as an article on URE's magazine "Radioaficionados" on
> January 2009*/
>
> Invented byJosé Salvador Luiz Victor Marinaro (PY2BBP) in 1957,

> this antenna is more than a dipole, it is a dipole with a passive
> element which works as a director or reflector element so there is a
> directional gain. Works from 20 to 6 meter bands. In 12, 10 and 6
> meter the passive element works as reflector instead of director,
> then a 180º rotation is needed to work the same direction.
>

> To build the elements can be used aluminium pipes of several
> diameters, linked and fixed by screws, to get the needed lengths.
> The dipole stands its two parts by a pvc pipe and a methacrylate plate.
>

> To feed this antenna a450Ω ladder lineis neededand antenna

> tuner too. Also a BALUN is needed which can be 1:1 or 4:1. Mine is a
> 1:1 current BALUN wound on a FT-240-43 core (12 bifilar turns).
>

> Ladder line length is important because according to the length
> you cut it and frequency, impedance values can be so high than the
> tuner cannot match. Minimum length is about 13.7 meters. Then I
> added a RG-213 to reach my radio room. This length must be also
> adjusted to be matched by the tuner with SWR 1:1. The following
> diagram shows the instalation.
>

> The ladder line must be insulated from metalic objects about 15

> to 20 cm. Can be replaced by two parallel RG-62(93Ω)coaxial cables,

> then feed line will be 186Ω.
>

> Map shows contacts I made when testing the antenna "Maria
> Maluca". In black color are 20 meter band QSOs, blue are on 17m. and
> red are on 15m. Mode was BPSK31 in all contacts, power 30-40W. The
> 80% of QSOs reported RST 599.
>

> *Technical data:*