Wire

Fan Dipole measurements with BU-50

Order of dipole wires top down

Most Fan Dipoles have a low to high band wire order (top-down). This might be the best solution, but I experimented changing the order. Putting higher frequencies between lower frequencies.

In this version the 20m wire is in the middle. So the order is:

Fan Dipole 160/80/60/40/20m

My third fan-dipole will be a more robust antenna than the previous more experimental ones. So therefore ... I will give up some higher bands (10m / 6m).

And, the 160m band must be included... (for many decades the lowest radio frequency band allocated for use by amateur radio)

Main goal is to end up with a fan of resonant dipole antennas on all the included bands.

My garden is to small for full-size 80m and 160m band dipoles, so I had to shorten and or fold (and even combine) some dipoles.

End-Fed for WARC

As the 30m band is CW-only, I will skip this band for the moment. I'm not (yet) a CW guy.

Leaving 17m an 12m to combine in one antenna.

Considerations

How to make the antenna resonant for both bands. The frequencies relate to each other as 3 to 4.

On the Internet there's lot of discussion about this End Fed.
One thread uses a full wave for 12m a coil and after that a wire of less than a meter to make 17m and 30m resonant. But how dus this work in theory?

So I dicide to start with one band: 17m.

Fan Dipole V2 measurements order 10/80/15/40/6/20m

This is the second version of the fan dipole.

Order of dipole wires top down

Most Fan Dipoles have a low to high band wire order (top-down). This might be the best solution, but I experimented changing the order. Putting higher frequencies between lower frequencies.

In this second version the 6m and 10m wires are swapped. So the order is now:

Fan Dipole V1 measurements order 6/80/15/40/10/20m

This is the first attempt for the fan dipole.

Measurements (SWR, impedance) after quick tuning of dipole wires to give a first impression. Not all dips on frequencies where I want them to be... 

Order of dipole wires top down

Most Fan Dipoles have a low to high band wire order (top-down). This might be the best solution, but I experimented changing the order. Putting higher frequencies between lower frequencies. Results shown below have this order:

Fan Dipole 80/40/20/15/10/6m

The Fan dipole for 40/20/6m performs well. Now it's time to extend the Fan with more bands.

I want to add dipoles for 80m, 15m and 10m. Making it a resonant antenna for all bands from 80m to 6m (except WARC bands).

Considerations

Adding more parallel dipoles will make the angle at the centre sharper for some the bands (the lower wires). This will affect the radiation pattern. It also decreases the impedance for those bands.

End Fed vs Fan dipole

These antennas can be compared on 20 and 40m. On 20m both antennas are half wave length. On 40m the Fan is half wave dipole, where the End Fed is extended and effectively a quarter wave, so about -3dB less gain.

Compare EndFed to Fan

Both antennas are about 10m above the ground at there feed point. Sloping down to about 5m above ground. Radiation direction is approximately North - South.

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer