Copyright © 1999-2011 by Harold Melton KV5R. All Rights Reserved.
Understanding Shortwave Antennas: Page 13
These are all the crazy “try it and see if it works” non-designed antennas. They usually work better than the telescopic radio antenna, but worse than the indoor longwire.
- House wiring: You can run a short piece of wire from the telescopic whip to the ground screw on the nearest electrical outlet, thus using the ground wires of the house as an antenna. The problem is that they go in all different directions and tend to cancel one another. But it’s the thing to try if you can’t even thumbtack a wire on the ceiling.
- Aluminum foil: KBOHAE reports that, “Aluminum foil can be used to make some very effective indoor antennas. Especially when these antennas must be physically short (less than ¼ wavelength). I have tried various antennas for shortwave listening over the years. The most effective indoor antenna that I have found is made from 2 or 3 strips of aluminum foil attached to the back of a world map. This antenna has outperformed any inside wire antenna that I have tried. It has also outperformed some outside wire antennas.” Thanks. This hadn’t occured to the author before, but a slab of foil on the end of a wire should electrically lengthen it, like the capacitance hats on shortened verticals.
- Hidden wires: If the ceiling wire is too bold for your landlord, you can run a long wire under the baseboard — just push it under (between the carpet and baseboard) with the back end of a butter knife. Works pretty good in upstairs rooms, but not worth the effort on the ground floor. The best hidden indoor wires are attic dipoles, stapled under the rafters, as shown on the previous page. They do require, however, access to the attic space, as well as a way to get the coax down to the radio. This is generally not for renters.
- Foil tape: If you are about to repaint, you can run a roll of foil tape along baseboards, then paint it. This works upstairs, and is the near-perfect hidden antenna.
- Gutters: Some building materials may be used as antennas, such as rain gutters. If it is metal and much longer than wide, it will work to some degree. Note however, that gutter joints tend to corrode and generate noise, particularly if you are near a broadcast transmitter.
- Thrown or draped wire: Buy a 100-foot roll of cheap indoor telephone wire ($8) and experiment with it. Run it out the window and throw it over the roof. Tie the far end to a tree. Twist all four wires together at both ends so it’ll act like one wire, not four.
- Compressed antennas: A 100-foot antenna may be erected in about 40 feet of space by using two metal “Slinky” toys. Run a nylon rope through the Slinkys. String it up in the available space. Stretch the Slinkys out as far as possible. Connect the coax to the Slinkys in center-fed dipole fashion. This a decent attic antenna for lower frequencies than space would otherwise allow.