A coaxial-cable trap dipole antenna installed in the attic provides a surprisingly effective solution to HF operation on the 10, 15, 20, 30, 40, and 80 meter

Il dipolo aperto e l'antenna più semplice, la più economica, la più facile da costruire

Si intende per antenna un dispositivo che è correlato alla risonanza, quindi che può contribuire attivamente alla selezione di frequenza

Dipolo, dipolo invertido, dipolo bazooka

Principalmente in ricezione e su tutte le gamme radioamatoriali ma anche più in basso

La Long Wire rappresenta un buon compromesso che permette di avere un’antenna multibanda

Half square o bobtail curtain, con un basso angolo di radiazione

The Bobtail-Curtain antenna is a monoband wire antenna which consists of three quarter-wave elements placed in a vertical plane, spaced half a wavelength and connected at their upper ends by a conductor

Initially tried to just throw up a length of wire, it kinda worked and i could hear a few more stations but it also pulled in a huge amount of noise generated by the nearby houses and electrical junk

Antenna for my interes mode CW on 40, 30, 20, and 15 meters

Richiede l'uso di un accordatore e di un balun 1:1

Using larger conductor diameters for the antenna like aluminum tubing rather than normally used #12 or #14 AWG wire can have an effect that will be different than using the calculator which is designed for normal wire use

Può essere realizzata tutta in cavo coassiale RG.213 o altro cavo

Il dipolo qui descritto è stato calcolato per risuonare nelle bande radioamatoriali dei 40m. 80m. e 160m

La prima parte, dal centrale o balun alla trappola, risonante sui 40 metri, che avrà una lunghezza di circa 9,90 metri per braccio, e l'ultima parte, dalla trappola all'isolatore, che porta in risonanza tutto il dipolo sugli 80 metri, con una lunghezza di circa 7 metri per braccio queste sono lunghezze che variano da installazione a installazione

It is important to erect the antenna as high as possible,certainly above surrounding roof levels

Questa antenna risuona sui 10-15-20-40-80

A Small Garden Antenna

The G5RV antenna is probably one of the most maligned antennas in the world

Most people think that the famous g5rv antenna was designed as a multi-band antenna, but in fact, it was actually designed as a three - half waves in phase antenna for 14 MHz

The invention of the G5RV dipole antenna, with its special feeder arrangement adder line is a multi-band

I frequently hear the question: how high should my dipole be? Or alternatively, will my dipole work well at this or that height?

It is a relatively cheap and simple way to have a decent low angle antenna RF performance, given its vertical polarization

I have had limited success with this antenna, although G3SWH has used this antenna for many years

As a result, the open feeding line runs tightly down and remains at a distance of about 20 cm from the mas

This antenna picks up signals best at right angles, it picks up worst end-on, therefore, remember to orient the wire to pick up from the direction in which you are most interested

Antenna bidirezionale per bande basse

Windom did some experiments and found that if the dipole feeding point was moved, the amplitude of the currents for the different bands was such as to have the possibility of resonance on the even harmonics

The G5RV antenna is named after the call sign of its creator, a radio amateur from England

have 1000 feet of open wire line, it is made from 4 awg stranded aluminum xhhw wire spaced on 5 inch centers, it is supported every 50 feet by 5 foot poles and there are 3 insulators between each support. zo = 450 ohms +/- 5%. the loss is .3 db on 160 meters including the transformers at each end

For the suppliers of 450 ohm open feeder. It is far easier to build this than find suppliers of this cable, and its a great deal less expensive

Back in the 1980's i built this rhombic antenna on an island owned by movie actor marlon brando

The simplicity of the inverted V-shaped dipole it consists of a half-wave dipole

Invented by dr. john d. kraus, w8jk, in 1937, it uses two dipoles, both driven and out of phase with each other, to create a directional antenna no front to back ratio, though that works on six bands 20-17-15-12-10-6 meters and as a top loaded vertical on 40 meters

A simple modification to a dipole wouldbe to add two λ/4 vertical wires, one at eachend, this is a half-squareantenna, the antenna can be fed at one cor-ner

A variation of the dipole is an antenna called a folded dipole. It radiates like a dipole but sort of looks like a squashed quad

Electrically the Zepp antenna has two parts, a half-wave radiator end-fed by a quarter-wave matching section connected to the radio

The following program will calculate the lengths needed to construct several popular wire antennas