16 Apr 2012

Homebase-6 (50MHz halo)

Homebase-6 50MHz halo prototype indoors ready for tests
This afternoon I had a go at scaling my Homebase-10 (28MHz wire halo) down to work on 50MHz. I simply scaled the dimensions by 28.3/50.1 (the ratio of the centre frequencies) and performance was almost spot on with a low VSWR in the DX part of 6m. So far I have only tried it in the shack holding the antenna in the air by hand and keying the TX to measure SWR. Next stage of tests will be to erect it in the loft space before erecting a more permanent version within the 10m halo on the top of the mast at the back of the house at a decent height. Still, a promising start. In the end I may opt for a small 6m beam like a Moxon or HB9CV though.

UPDATE 1600z : I have now erected this horizontally in my loftspace although it is more triangular than square. Match is good so I'll see how it performs locally next.

UPDATE 2100z: I am surprised that I'm unable to copy the more distant UK 6m beacons such as GB3BUX and GB3RAL which use horizontally polarised antennas. I need to monitor for longer to see if they appear by MS or tropo.

2 comments:

David Cope said...

Interesting.

I'm in the process of moving, if I manage to get the property I've just looked at (it's rented) then I'll maybe get one shot at putting one (small antenna) on the roof.

This may be an option. I'd like to work 6m FM too - it's a real problem having to choose polarisation too isn't it?

73, David G8JGO

p.s. If I managed to get this through the new Captcha - it's playing havoc with my dyslexia!! The old one was better (for me anyway). (2 attempts)

g4fre said...

I have a 50MHz halo in my loft, with this i can copy gb3baa, gb3bux gb3ral 90% of the time and gb3bux through severe qrm 40% of the time
Dave

Similar results are obtained with a 70MHz version

Dave

g4fre
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