Welcome to Tropical band

To most people the phrase "tropical bands" bring a pretty clear picture to mind - a bunch of shirtless guys playing calypso music. But to experienced shortwave DXers those two little words express the most challenging and enjoyable part of the radio hobby. The phrase kindles memories of a DXer's best catches and favorite QSLs, of exotic stations, music and of early morning listening sessions. (Don Moore)
I like the "Tropical band" name for new 60m allocation. (OK1RP)

Effective from 1st Jan 2017 please paper QSL via OM-bureau only.


Saturday, January 15, 2011

Short dipole for 60m Tropical Band

By Enrique A. Wembagher, Argentina
HCDX Antenna Special, 1 August 2004

This is an antenna specially calculated for the tropical 60 meter band, with instructions for those who do not possess a lot of space at their locations.

This antenna is a short dipole made up of inductores (L1 /L2) in half of each arm, based with the concept of inductive load.



The dimensions are shown in the figure. The L1/L2 can be built on tubes of PVC; the feeding slope to the radio can be either coax of 50 or 75 ohms.

Construction

Antenna: A total of 12 meters of wire, with a diameter of about 2 mm, divided into four sections. Insulators cn be of porcelain or PVC. To fasten the antenna one can use, thread of clothes for the anchorage.

L1/L2: Two tubes of PVC of 5 cm (2 inches) of diameter and approximately 20 cm of longitude. Roll 60 turns of wire of 1.5 mm on each tube, closely wound. A length of 10 meters of wire should be sufficient for each inductor.

The diagram above show the disposition of the antenna with its respective inductors L1/L2.

By Enrique A. Wembagher, Argentina

6 comments:

  1. Looks like a good idea. Would only take elements about 37 feet long to have a rotatable dipole if designed to have the antenna strapped to bottom of lightweight PVC material for the support needed. HI You would neet a "truss" support at the center to help keep the PVC from sagging badly. May do this during upcoming Spring/Summer better weather.

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  2. San,
    thank You a lot for comment my friend. Yes if it will be mounted enough high then it can be good solution. Only the problem can be with big coils losses. On-air test results will be interesting.

    73 - Petr, OK1RP

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  3. This comment has been removed by the author.

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  4. L1/L2: 50 or 40 mm?
    I think that: 50 mm for 4 MHz and 40 mm for 5 MHz.
    ¡Aprox!

    73 from Spain.

    www.ea7hfg.com.es

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  5. Hello friend,

    according to the original source here:
    http://www.hard-core-dx.com/nordicdx/antenna/wire/60mtrapdipole.html
    the L1/L2 coils diammeter should be 50mm.

    In my opinion it is not so critical. The inductive load will extend the electrical lenght and depends to actual coils inductance (and antenna location) the resonance must be adjusted by changing the lenght of both legs...

    73 - Petr, OK1RP

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  6. Hi ive only got the white pvc but its 40mm will that be ok to use...? guess the legs dipole may be a bit longer?
    cheers
    paul

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