G4ZTR.co.uk
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70 MHz

4m squares worked to date (195). With the Perseids coming up shortly, can I reach 200 this year ?

I like 4m and I always have done! In recent years, the availability of the band to a good number of European Countries has increased my interest further.

 

There are seldom tropo enhancements on the band, but most other forms of propagation occurr: Sporadic E, Aurora and Meteor Scatter.

This was my early LFA for 4m. I now run a 6 ele but the picture has escaped. The LFA does exactly what it says on the tin.
Inside my FT-847, before installing the G4FUF 4m preamp
....... and after. No 4m user should be without one !

Aerials for 70MHz

There is a surprising variety of beams available for 4m. The chart below is stitched together from manufacturers information. Gain is what the maker claims. Front to back is not quoted because different makers measure it in different ways, making comparison difficult.

 

There are even more aerials from InnovAntennas than I have included, but I stopped running down the list beyond an 8 ele with a boom length of more than 8m.

 


Maker Model Elements Gain dBd Length m
InnovAntennas 2el LFA2 2 4.4 0.6
InnovAntennas 2el LFA-Q 2 4.7 n/a
InnovAntennas 3el OWL 3 4.8 0.8
Vine 4m3DXS 3 5.7 1.4
InnovAntennas 4el OWL 4 6.3 1.7
InnovAntennas 3el LFA-Q 3 6.5 1.2
PowaBeam 4CQM5UC 4 6.6 2.1
InnovAntennas 3el LFA 3 6.6 1.4
InnovAntennas 5el OPT-DES 5 7.0 2.0
InnovAntennas 4el LFA 4 7.7 2.1
Vine 4m4DX 4 8.3 2.6
InnovAntennas 5el OWL 5 8.3 1.3
I0JXX 5JXX4 5 8.5 3.4
InnovAntennas 5el LFA 5 8.5 3.1
Vine 4m5DX 5 8.6 3.4
InnovAntennas 6el OPT-DES 6 9.0 3.4
PowaBeam 4M5N50U 5 9.1 3.0
InnovAntennas 6el LFA-ZTR 6 9.2 4.4
InnovAntennas 6el LFA 6 9.7 4.9
PowaBeam 4CQM7F 7 10.0 5.0
PowaBeam 4M6N50U 6 10.3 5.0
Vine 4m6DX 6 10.4 5.2
InnovAntennas 7el LFA-WOS 7 10.9 6.8
Vine 4m7DX 7 11.0 6.6
InnovAntennas 8el LFA2 8 11.4 8.3
Vine 4m8DXX 8 11.5 8.3