Magnetism and Reception

[Tripredacus]

This is something I learned at least 10 years ago. I had a small black and white TV that used a coat hanger for an antenna. The reception was poor. I put a magnet on it and the reception was great.

Why are commercial antennae only large peices of metal? Why don't they use magnets?

A couple months ago, I decided to use a larger magnet from a busted subwoofer, at work to amplify the antenna at work. This was a simple console AM/FM receiver that had a simple antenna. It was withing a room in a large warehouse. The building acted as a dampening field, making some stations not come in at all. Now using extra wires and this magnet, we can get a station we would never get in, all day.

Today, at home, I finally was fed up. I do not have cable or satellite, and frankly while I could afford it in the summer, the gas prices (for heating) in the winter would make it impossible. And if you aren't in the US, we do not have over-air analog broadcasts anymore. So I have a Digital TV tuner box hooked up to my TV. When you get one of these, it does not come with an antenna. I was using just the one I had for my TV before the switch-over, but I would get artifacts on all channels, making watching TV totally useless.

I had wondered if I could duplicate my success in using magnets to lure in radio waves with HD Over the Air broadcasts. The answer is yes.

Today would end that situation. I used a busted speaker, my original antenna (its the one that looks like a bowtie and connects with 2 screws), a Radio Shack antenna box (coax -> 2 screw antenna), a coax cable and a M2M Coax connector to make my new antenna. And it works great.

What I have now, is a magnetic field as an antenna, just as at work. At work its a problem. I have already determined that we can move carts around the room to increase/decrease reception. At home that shouldn't be a problem!

So why do they not put magnets into antennas?

[GrofLuigi]

So why do they not put magnets into antennas?

Because it would magnetize the screen? (No matter how much you warn them, people will put antennas on top of the TV set).

GL

[dencorso]

Today would end that situation. I used a busted speaker, my original antenna (its the one that looks like a bowtie and connects with 2 screws), a Radio Shack antenna box (coax -> 2 screw antenna), a coax cable and a M2M Coax connector to make my new antenna. And it works great.

Would you please post a pic of your homemade antenna? Thanks in advance.

[Tripredacus]

I'll bust out the camera when I get home.

Here are some pictures. The first you can see from the left is a standard co-ax cable. This ends up getting connected into the tuner box. It is the grade used for Cable TV, not satellite. It also isn't a high quality one, but it was the only one I had. It connects into a standard Radio Shack RF adapter. I needed this so I can hook up the next thing, which is an old "bowtie" antenna.

http://i85.photobucket.com/albums/k63/Trip...os/DSC00007.jpg

Next I needed to connect it to a magnet. I find the easiest and best place to get a good powerful magnet (for free too!) is from a broken speaker. Not all speakers have good magnets. For example, the monitor speakers from an Old Packard Bell won't work. If you want to know if the magnet is good, try picking it up with a screwdriver! This speaker was from a bookshelf speaker that drowned in my basement flood earlier this year. You can tell from the rust on it. I have an alligator clip there to make sure the bowtie doesn't fall off. Even tho it is a strong magnet, the bowtie is thin, so the area to be magnetised is small as well.

http://i85.photobucket.com/albums/k63/Trip...os/DSC00008.jpg

It took me quite awhile to find the right amount of adapters and parts to use. And also bearing in mind that I didn't want the magnet near the television either. I had to change my original hookup because I did not have an extra co-ax cable. Originally, my tuner was connected to my VCR using the coax from the first pic. I wouldn't have needed it if I hadn't misplaced one of my adapters... Now I changed it so my tuner box is connected using Composite to my VCR. So this is my great TV set-up now:

Magnet antenna -> Tuner via coax

Tuner -> VCR using Composite

PS2 -> VCR using Composite

VCR -> TV using high-grade coax

VCR -> speakers via RCA cable (Composite minus yellow cable)

I'm in a situation where I can't afford to get cable, fiber or satellite TV. The summer time wouldn't be a big problem, but the winter time the heating cost makes it impossible. So I make do with what I have!

ps: maybe this should be in the Hardware forum?