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EFHW the end-fed half wave antenna


EFHW as an ideal temporary antenna for the hiker or camper. Ease of installation appeals especially to me because of my long life of sorrows trying to get lines through trees. I don't have a pitcher's arm and I've proven to be fairly inept with various slingshots and other antenna raising contrivances. Amazingly enough, just one good shot over a 20 foot limb can be all it takes to put up a quite functional 40 meter EFHW in an inverted vee configuration
post 01 Mar 2024
EFHW the end-fed half wave antenna

Antenna End Fed Links

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EFHWA tuner
Un tipo un balun 1:7 oppure 1:8 per fronteggiare gli ohm presenti ai vertici della nostra antenna, quindi 3 giri di avvolgimento primario e 21 o 22 di secondario andranno bene. per quanto riguarda il ROS non salgo mai sopra 1.6-1.8

Endfed per 17-20-30-40 metri
Una veloce multibanda E.F.W.H.A. dedicata ai piccoli quadri banda come il mio FT857D

End fed 1/2 wave matching system end feed
End-fed antennas are increasingly popular again, at least partly because of compact iron toroid cores. Small soft-iron cores allow compact, easy-to-build, low-power transformers and networks

End fed antenna lambda/2
Un trasformatore 1:64 su cui e' collegato un filo lungo lambda/2 della frequenza prescelta. una versione a 3 o 5 bande in modo da avere maggiori chance su piu' frequenze. Un filo di rame teso ha un'impedenza superiore ai 3.3 K ohm e quindi per poter adattare l'impedenza ai 50 ohm della radio, con un toroide FT240-43 - 1:64

An EFHW antenna for 160-10m band
An efhw as inverted-l from the feedpoint at the edge of property, about 10m upwards into the direction roof ridge


Take off angle of horizontal antenna

Take off angle of horizontal antenna For horizontal polarization, the electric field will move sideways on a horizontal plane, while for vertical polarization it will oscillate up and down on a vertical plane

Rx antennas 4Square Rx Vertical Array

Rx antennas 4Square Rx Vertical Array My frequency design of 1.825 MHz a 90 degrees line would be 33,70 metersinstead of the previously calculated 33,27 m

Calculo da Antena Bazooka

Calculo da Antena Bazooka A double bazooka antenna is a combination that has a complete coaxial wave multiplied by its velocity factor and a total end-to-end length of 1/4 wave for each side affected by another driver shortening facto