Copper wire for external AM/SW Antenna

Years ago I lived for a few years in the Snowy Mountains and had one of those basic General Electric long range raidios. I used a roll of galvanised tie wire from a hardware store for an aerial and earthed the radio with a short length of automotive wire to the earth point of the house.

The insulators were little ceramic cotton reel style things from the hardware store. They are just a connector designed to join two wires without letting them touch each other. I put one at each end of the aerial then ran another short wire from each insulator to the facia boards on the house and as high up a tree as I could get. Another length of automotive wire connected the aerial to the radio.

The whole thing might sound primitive but it picked up Sydney stations perfectly day and night.

Brian

Hi Mick,
A lot depends on whether you are talking about a permanent (at home) or a temporary (out bush) installation.

However, a few comments about the requirements. I know that these are in the user manual, but I agree that they are a bit confusing.

1 & 2) "Optimally 500 Ohms" and a Good Place to Buy
What this means is that the antenna impedance (sort of like resistance) needs to be "high". In radio terms, this impedance is actually measured between the antenna and the ground.

In a temporary installation, to meet this requirement, all you need is some hookup wire connected to just the antenna socket.

I have a roll of hookup wire that I bought from Jaycar. It's
13 x 0.12 tinned hook-up wire. Look at catalog item WH3001 as an example. I know it's only 25 meters, but that is fine.

Dick Smith will have similar wire, but DS tends to be a bit more pricey than Jaycar.

When out and about, I just throw one end up a tree, or if no trees across the top of the tent on the camper.

At home I have a similar arrangement, but is has been broken a number of times in strong winds. For a more permanent installation, something heavier duty is required. Jaycar has plenty of choice, but don't go overboard with expensive wire (Don't use Coax cable, it's not needed).

3) Non Conductive insulators
All these are is something that insulates the antenna wire where it is tied to any supporting structures.

If it is insulated wire, nothing extra is required, except if it is subject to wear, in which case something like a loop of nylon rope where the wire is supported / tied will be sufficient.

4) Ground Socket and Ground Rod.
The "Earth" connection actually provides the other "half" of the antenna.

If out and about, often I don't use anything, but the advise to use another length of wire laid on the ground will do the job.

If at home, just connect to a metal water pipe with the same time as wire as the antenna, this should be fine .

Cheers and Happy listening,

Mal

1. The nominal impedance for any end fed wire is a function of the frequency. A wire a quarter wavelength long will have an impedance of between 38 and 60 ohms.
2. No idea apart from a trade electrical outlet.
3. Ones made from non conducting material (glass, bakelite, PVC)
4. No.

Thanks Mal and footloose....very helpful info there...Mal, the use for me would very most probably be always 'temporary'...mainly for use out bush....now and again at home.

Thanks again...great answers.

Cheers,
Mick.

Why not go to a auto parts place and buy a 30m roll of 3 or 4mm insulated wire.......you can even get it in a choice of colours too.

I would not worry to much about resistance as most general coverage recievers have a strong front endand will recieve with a piece of wet string.

Forget signal lose on your general coverage reciever.

If these thing really concern you get rid of the Grundig and get a real reciever like a Icom 8500 or something good.

Regards Richard

Thanks for the input all...!!!. Have a very confident starting point now. I will try the jaycar wire bizzo first Mal, Do i just put one end in the radio the other end up one tree vertical...or is it important to try and get the wire to go horizontal as well (across 2 trees)?.

Ill also try brians snowyriver thing to fartass around.

Have no idea what you mean by 'strong front end' Richard...but will not worry too much about signal lose.

The main reason I want to try and improve signal is when out and about at places over the last few years, I use radio to try and listen to the footy on AM (or SW if cant get signal on AM), most time I get it....BUT always keep losing the signal or very weak and scratchy....especially some places around cape york, kimberley, any of the deserts...etc....etc.

Thanks again, cheers,
Mick.