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.

Schema

Schema Fam dipole 160m-80m-60m-40m-20m

See pdf below on this page for full size schema

 

Considerations

Most Fan (parallel) dipoles found on the Internet start with the lowest band (longest wire) at the top. Bands are added in sequence. Highest band (shortest wire) at the bottom.
Maybe it's a good idea to 'un-sort' the order. By this the longer wires are more apart so reducing mutual influence. 

Center fed antennas fed with coax (50 Ω) will need a balun. I use the 1:1 BU-50 Balun from Diamond.

Limitations

My garden is too small for a full-size 80m (and 160m) dipole. At one end there is space for 16 meter wire. On the other end 12 meter. Just enough for a full size 60m dipole .
Adding a coil - plus some extra wire - at the end of each dipole-wire for 160m may be the solution.

In a earlier fan-dipole the 80m dipole was extended with one coil in the shorest wire.
The experiment is to see if it will be possible to combine the 80m and 160m bands in the same wire. 

Center mast 10 meter high. Poles at the end about 5 meters high. So it will be a Inverted V Fan antenna.

The BU-50 balun is specified from 1.7MHz to 40MHz. Probably not the ideal balun for 160m. We'll see...

Some dipoles (80m and 160m) will be somewhat a-symmetric. This influences the feedpoint impedance for that bands.

As 16 meter wire (on the left side) is only somewhat to short for 80m it's not necessary to extend that side on 80m. Side effect is that feedpoint will be somewhat off-center.

Construction

 

Fan dipole 160m-80m-60m-40m-20m

 

Extension coils for 80 and 160m bands
Extension coils for 80 and 160m bands

 

BU-50 BaLun and RF choke
BU-50 BaLun and RF choke (RG-58 on 240-43 core)

 

130uH 20mm coil for 160m
130uH (20mm) extention coil for 160m

MeasurementsSWR 160m

 

 

 

 

 

 

Full-size schema:

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