extension cord longwire

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7designs

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Interesting thought for a make shift antenna, has anyone used a 100ft extension cord as a sw antenna?

Of course it would be cheaper and better to go buy 100ft of wire, but just looking at one I wonder how it would preform?

What about antenna mast guy wire?
 

ka3jjz

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I would choose the extension cord over the guy wire; it would be easier to work with the extension cord (guy wire is usually pretty stiff). Just be sure to seal the ends so moisture doesn't work its way in.

That's the nice thing about receive antennas - damn near anything can be made to work and you'll hear something.....best regards..Mike
 

JnglMassiv

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I'd certainly make sure the male end was at the radio. Anything to reduce the chance of someone plugging it into the wall outlet!

All things equal, it is desirable to use copper conductors for the antenna. This would give the extension cord the nod over a same-sized steel guy wire.

For receiving, I'm not sure if you'd see much benefit to connecting all of the conductors or not. If you were transmitting, I'd connect them at each end of the cord.
 

nanZor

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One interesting trick you can try when using dual-conductor cables, is to short the far end of the cables together, and at the receiver, just connect only side of the dual-conductor pair. Snip away an inch or two of the unused side at the receiver.

When you do this, you now have "linear loading", which might prove useful on the lower bands, especially if you don't have a very long antenna to begin with.

If you have access to the ends so you can short / separate the conductors, you have a tricky little dual-bander. :)

I've found this trick to be very useful for those times when antenna space is at a premium, and didn't feel like winding a loading coil.

It isn't the most efficient linear-loading antenna you can make, but it can get you in the ballpark. Zip / lamp cord works, but the efficiency goes up as the spacing gets a bit larger, such as with twinlead, or open-wire line.
 
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ridgescan

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This illustrates what Mike ka3jjz said about the fact you can utilize just about anything as an SWL antenna. I have always told new people here that you can even use a metal tape measure as a SW antenna and it does pretty good! Matter of fact Sony makes a reel type SW antenna based on the same idea. Note in this video, that before I connect the tape measure to the radio's built in whip, that I have that built in whip plus another whip plugged into the back antenna jack getting the initial signal. Also note that I ran the tape measure out a mere 14 feet and that still made a significant improvement to the signal:)
YouTube - Metal Tape Measure SWL Antenna

So OP you can have fun experimenting with different stuff right inside your home, of course there's no sub for a good outdoor wire but as you can see, you can do some serious SWL indoors too.
Edit-the secondary time blips you hear as I walk towards the cabinet is CHU Canada playing on the R71A in the bedroom:)
 
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K9WG

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And for portable antennas there is always the:

Frank's N4SPP Ham Radio home-built slinky coil dipole antenna
radio-slink-ant1.jpg
 
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