Limited space horizontal loop for local 80M ops
Ian White GM3SEK wrote:
ferrymanr wrote:
Remember that this has to be a 'stealth' antenna as I live dead center
in the town with a lady councillor opposite, the town council office
75 yards away and town hall about 150 yards away. This rules out low
loss copper pipe etc. Most of the small 'magnetic loop' antennas are
intended for vertical use which would also stand out like a sore thumb
here.
It's surprising what can be done, with a bit of determination that you
*are* going to get on the air.
I know a ham who lives in a Listed building, which means he can hardly
even paint a door without consulting the local Council's Conservation
Officer. To make life interesting, he lives right next to the Council
offices, and there's a perfect view into his backyard from the
Conservation Officer's desk! Now that's what I'd call really living with
restrictions... yet he has still found ways to get out well on 80m.
(His antenna would be very unlikely to suit your situation, so there's
no point in describing it in detail.)
Always remember that you have rights too. With certain exceptions, most
UK householders have the right to put up a garden shed without asking
anybody's permission at all. A surprisingly large shed, too - with a
pitched roof, the ridge could be up to 4 metres high.
Check how that would apply to you. And then, if anyone objects to you
using a 4m high vertical loop, ask them if they'd seriously prefer that
you build a whole big shed around it?
The advantage of the wire loop is that many buildings here have wire
around the roof to deter seagulls, that means my wire would not be
conspicuous.
That would certainly be another option to explore; but whatever you do,
be sure to make the best use of all your rights.
I would transmit on an efficient short vertical, and use a magnetic loop
on Receive. For that matter any low noise receive antenna like a Flag
or K9AY. I would also look at something like the Welbrooke Active loop.
I wont get into the debate of "magnetic" and noise! Just go to
Welbrookes web page and read some of the reviews from a EMC expert on
noise and comparing the Welbrooke to 20,000 Dollar R&S EMC antennas E
and H plane antennas.
If W8JI and others can work DX on 160meters from an efficient mobile
antenna, you should have no trouble getting out. There was a guy on 80
meters from the west coast K6MB who used to beat stations with dipoles
in the 80 meter DX window with a coil loaded mobile antenna!
Dont believe all the high angle low angle nonsense, the difference in
real terms amounts to one deep fade. I would never feel at a
disadvantage running a vertical versus a low dipole.
There was a interesting article in QST by Some PA hams who used a R&S
super resolution DF antenna and measured incoming arrival angles across
Europe, oh how i would like to have one of those setups! They use cross
loops too.
Zen
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