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 Wire antenna advice restricted space 
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Post Wire antenna advice restricted space
Hi, looking for a bit of advice please, I'm looking at installing a wire at my house it would be about 18ft height around the corner of the building around about 12 m in lenght, I have been looking
at end fed antennas, traped dipoles etc.

Idealy it would be nice to cover as many HF bands as possible, any advice would be most welcome


Simon.


Fri Feb 15, 2019 1:36 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
.

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Last edited by G4LNA on Fri Feb 15, 2019 2:17 pm, edited 1 time in total.



Fri Feb 15, 2019 2:05 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
MW6ORF wrote:
Hi, looking for a bit of advice please, I'm looking at installing a wire at my house it would be about 18ft height around the corner of the building around about 12 m in lenght, I have been looking
at end fed antennas, traped dipoles etc.

Idealy it would be nice to cover as many HF bands as possible, any advice would be most welcome


Simon.


A diagram would make it easier to comment, including if you could put a pole away from the house, at the moment I get a picture of it up against the house going round a corner (the antenna not the house).

Can you put it over the house, even if it is on the roof?

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Fri Feb 15, 2019 2:11 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
A small, efficient multiband antenna is like the Holy Grail.

Better to choose just a couple of bands (say, one ''day' band and one 'night' band} and 'optimise' as much as space allows.

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Fri Feb 15, 2019 2:19 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
thanks for the replies I have taken a couple of pics and added the measurements


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Fri Feb 15, 2019 3:14 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
20 metre OCFD?
http://www.m0zpk.co.uk/40-meter-off-centre-fed-dipole/

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Fri Feb 15, 2019 3:23 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
For multi band, this would be my first try

If you can let a few feet hang down in the corner near the door, it would help


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Fri Feb 15, 2019 3:36 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
Thank you everyone for the helpful replies, Sangoma thinking about going with your advise thankyou
would you buy a ready made one or buy an 9/1 unun and get the wire yourself ?

Simon


Fri Feb 15, 2019 10:34 pm
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
MW6ORF wrote:
Thank you everyone for the helpful replies, Sangoma thinking about going with your advise thankyou
would you buy a ready made one or buy an 9/1 unun and get the wire yourself ?

Simon


I wouldn't consider buying one, however each to their own ideas.

There are three windings, easier if you use three different colour wires (or spray paint two of them different colours)
For 10W you could use three strands of an old cat5 cable or similar

Use a type 43 toroid and .7mm "magnet wire" or 1.2mm if you one day need 100W, and the 140 core. The 240 core is advisable for 100W digital/FM

https://www.radio-store.co.uk/13-ferrite-cores

It looks as if you may want to try more than one solution, so I would suggest making it yourself, as you can also try other ratios of unun. It is well worth it, and a ordinary 9:1 or 4:1 would take less than 10 minutes once you have found your way of making them.

What is round the corner to the left? Could the vertical part go there? Ideally the total wire length needs to be around 66', though that may well change being up against the building (so might performance, especially if there is steel work in the walls).

You may also find this very useful http://www.foxdelta.com/products/aaz-0217.htm comes to $64 including postage, easy to assemble if you like soldering, though they usually offer them for about $10 more to include assembly.

This will give you a sweep on your PC of the SWR from 1mHz up to 60mHz, you can compare 3 sweeps, so take one, make an adjustment, take another one and see the result of the change. Cheaper and easier that any other analyser for the purpose.
The HF bands are highlighted on the graph, which is a big help.

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Sat Feb 16, 2019 4:34 am
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 Wire antenna advice restricted space 
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Post Re: Wire antenna advice restricted space
If your after a good quality 9/1 un/un there are a few left over from a commercial Rhombic antenna order on ebay
https://www.ebay.co.uk/itm/233129648009 ... 1555.l2649

9/1 Commercial Professional Un/Un, multi-core Mil PTFE wound, UV protected enclosure and resin potted, PTFE socket, 125 watts pep handling, fitted with condensation hole, Stainless Steel strain reliefs for lines, manufactured for overseas Commercial antenna Company for HF Rhombic antennas, individually serial number, individually checked and swept on Network Analyser/Antenna analyser and on air tested. Limited quantity as these few were left over from a Commercial order this month. and FREE post for £28

:-)

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Wed Feb 20, 2019 10:16 am
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