Message-ID: <9E1D0F6DD9224C7A86D4227122F486E5@MLB>
From: "Martin Evans." <books@mollies.freeserve.co.uk>
To: <rsgb_lf_group@blacksheep.org>
Date: Thu, 9 Jun 2011 11:07:55 +0100
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Subject: LF: antenna for 137kHz.
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Gentlemen - some advice, please.

My radio room is in a bedroom at the back of my house.

Currently, I use a wire running from the bedroom up to a pole on the chimney about 35ft (10m) above ground, 
then to a pole at the bottom of the garden about 100ft (35m) away, then down to the bottom of the pole, where 
it is tied off.

I tried running the wire back to the house (end not connected to anything)  at about 8ft above ground (2.5m) 
but this runs alongside a long building with my office, with electicity cables, computers, etc, so it picked 
up a lot of noise.

The signals seem "cleaner" when this return run is cut off.

How can I improve this setup?

I am thinking of pulling the far end of the wire over to the other side of the garden and running it back to 
the house there, probably about 10ft (3m) above ground, then back inside to make a loop.

I would then have a loop aerial in a 45 degree plane, roughly.

Does this sound as if it could be an improvement over my current setup? Would lifting the bottom of the loop 
up to be more horizintal be better or worse?

Any other suggestions?

My garden runs roughly East-West. Does my current "Inverted U" aerial have any directivity at this frequency 
(137kHz)? What would be the directivity of my proposed 45 degree loop?

Thanks for any help & suggestions,

Martin  GW3UCJ deep in the Swansea Valley!