Cette page était sur le site de G3YCC; mais le
lien ayant disparu, j'ai reproduit ici l'article que j'avais
THE LATTIN 5 BAND ANTENNA (FOR 80, 40, 20, 15 AND 10 METRES)
The antenna was named for W4JRW who invented it and holds a patent on the basic principle and uses quarter wave stubs, which act as insulators at the frequency for which they are cut. For example, the 6'11" stub (quarter wave times the velocity factor 0.8 of the feed line used) blocks RF for 28 mhz from reaching the rest of the antenna.
In the example shown in the diagram, tubular foam filled 300 ohm feed line was used, which has a VF of 0.8. Other feedlines may be used, for example, slotted ribbon and the length of the stubs worked out using the correct velocity factor
BUILDING THE LATTIN ANTENNA
This will require some forethought and planning. Avoid cutting the continuous top wire, which supports the whole system. I wonder if it might be an idea to use a suitable polypropylene line to support the wire, which may be subject to breaks, especially at the solder points?
A suitable centre piece may be constructed and constructors may want to include a balun at the centre of this balanced antenna, which is fed with unbalanced line (coax).
If you do have a go at this, please let me know - I have always wanted to make one and never as yet got round to it!
A version of the Lattin could be designed for all bands, including the WARC bands - get snipping!
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