A simple way to electrically lengthen a short wire is to add a coil inductor to the wire.
Got one laying around? Don't have the parts / time / knowledge to make it a high-Q version? Will you be kicked out of the house with that contraption indoors?
Try linear loading. NO, it is NOT as effective as a lumped inductor coil, nor a panacea to all ills. There are plenty of references as to why this is so. Typically you can expect about a .6 to .7 shortening or so as compared to a regular wire, or just a lowering of the resonant frequency.
Basically, linear loading is merely folding a wire back on itself. So instead of using say a 30-foot random wire, try using a 2-wire element folded back on itself.
Example - using speaker wire (or any other 2-wire cable) roll out 30 feet (or whatever you have) Connect the far ends together. At the receiver end, connect only ONE side of the wire to the antenna input jack.
More precisely, you can get in the ballpark with 150 / f Mhz for a quarter-wave element measurement. Dipoles, try 300 / f Mhz. This obviously differs from the standard equations for quarter waves and dipoles since we are now loading the elements.
Nearly all the same rules of physics apply - ie you still need a good ground for verticals, etc, dipoles should be high and in the clear - or just do the best you can.
So if you are short on space, try linear loading your wire and have fun while hitting the books to see where it excels, and where it falls short.
The first tip is that if your wire is extremely long, at some point you'll run into a lot of loss resistance. I typically don't linear load wires longer than about 75 feet from end-to-end. But don't let me stop you from experimenting!
Got one laying around? Don't have the parts / time / knowledge to make it a high-Q version? Will you be kicked out of the house with that contraption indoors?
Try linear loading. NO, it is NOT as effective as a lumped inductor coil, nor a panacea to all ills. There are plenty of references as to why this is so. Typically you can expect about a .6 to .7 shortening or so as compared to a regular wire, or just a lowering of the resonant frequency.
Basically, linear loading is merely folding a wire back on itself. So instead of using say a 30-foot random wire, try using a 2-wire element folded back on itself.
Example - using speaker wire (or any other 2-wire cable) roll out 30 feet (or whatever you have) Connect the far ends together. At the receiver end, connect only ONE side of the wire to the antenna input jack.
More precisely, you can get in the ballpark with 150 / f Mhz for a quarter-wave element measurement. Dipoles, try 300 / f Mhz. This obviously differs from the standard equations for quarter waves and dipoles since we are now loading the elements.
Nearly all the same rules of physics apply - ie you still need a good ground for verticals, etc, dipoles should be high and in the clear - or just do the best you can.
So if you are short on space, try linear loading your wire and have fun while hitting the books to see where it excels, and where it falls short.
The first tip is that if your wire is extremely long, at some point you'll run into a lot of loss resistance. I typically don't linear load wires longer than about 75 feet from end-to-end. But don't let me stop you from experimenting!
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