What type of metal are home television and radio antennas made of? Is this type of metal the best metal for quality reception?
I am referring only to the “rabbit-ear,” “butterfly,” telescoping, and ring type. Additionally, rooftop tv antennas. NOT dishes!
I’m pretty sure that they’re made of aluminum. Ideally, you’d want the best conductor you could get, which would be silver, or barring that, copper. However, aluminum is still pretty good, and it’s much cheaper than copper or silver. Silver might be used in a few cases, such as the military or the space program, where quality is essential and money is no object, but don’t expect to see it in your TV, for obvious reasons.
Oh, yeah, it’s also considerably lighter, so you don’t have to make it as strong to hold its shape.
Aluminum was my first thought. So why can’t I just connect some copper tv antenna wire to the aluminum siding on my house, then to my televeision and get a crystal clear picture? One would think that would be one big ass antenna.
Rabbit Ears and other telescoping antennas are most commonly Nickle-plated brass. That is very common and inexpensive for electronics, and the nickle doesn’t readily corode, thus keeping a nice finish and the ability to still telescope easily if needed.
The “ring” and “butterfly” antennas, I am guessing, tend to be steel…again, often nickle plated.
Rooftop antennas are most commonly made of aluminum, sometimes anodized.
For one thing, your sidings are probably grounded - i.e. has a conductive path to the earth. Any current induced by the radio waves would just flow straight to the earth instead of into your TV.
If you took care to insulate it from ground, it would probably work, but it will still be worse than a properly designed antenna. There is an optimal length (1/2 wavelength?), and also the typical Yagi antenna design (ones that look like fish skeletons) have other elements to optimize the sensitivity.
wouldn’t having an entire hunk of your house as a receiver introduce a lot more ghosts and other interference?
All outdoor TV antennas are made of aluminum. It doesn’t rust, is inexpensive, is light (weight), and a good conductor. No other material can compete.
Won’t work…
The effectiveness of an antenna does not depend on mass or surface area.
Without getting into too much detail, an antenna is not just a “blob of conductive stuff”; it is a tuned receiver (or transmitter) of electromagnetic fields.
Believe it or not, your lowly TV antenna atop your roof is actually a carefully engineered device. The absolute & relative lengths of each element, spacing between elements, direction, etc. all work together to maximize efficiency (i.e. gain) and directivity. Other factors such as bandwidth and impedance also come into play.
People have been trying to optimize antennas for over a hundred years, and it is still a black science, in my opinion. I still don’t have a good understanding of them. But I’m glad some people do.
Indoor rabbit ear, butterfly and ring type are typically stainless or chrome plated steel. Some larger indoor UHF antennas (Radio Shack type square grid with wings) are aluminum on a steel frame.
Indoor FM “T” antennas are plastic coated copper.
Rooftop antennas are typically aluminum.
Per other posters metal conductivity/quality, within limits, is secondary to engineering design issues.
There was a device sold about 20 ++ years ago that employed a similar principle of using the house wiring as an antenna. It plugged into a wall socket and drew RF from the house wiring loops. Despite the mass of conducting material it was an awful antenna (probably dangerous too) in most cases per the aforementioned ghosting problems inherent in a non-directional antenna.
“Here let me adjust that antenna” …BZZZAAPPPP!
chronos said
I’m pretty sure that they’re made of aluminum. Ideally, you’d want the best conductor you could get, which would be silver, or barring that, copper. However, aluminum is still pretty good, and it’s much cheaper than copper or silver. Silver might be used in a few cases, such as the military or the space program, where quality is essential and money is no object, but don’t expect to see it in your TV, for obvious reasons.
Oh, yeah, it’s also considerably lighter, so you don’t have to make it as strong to hold its shape.
Sorry Gold is the best conductor.Silver tarnishes easily as does aluminum. They use a plastic like coating to keep it from tarnishing. They also use a alodine solution(or maybe it is anodine) also.
Some of the military replacement resistors I helped manufacture back in the 70s had gold plated leads and they are still shiny. We used to use a type of gold paint to provide the best electrical connection when capping the ceramic. The lead is then welded to the cap.
Hi me again
Crafter man is right. It is a precise science but with many variables.
My uncle used bed springs and danmed if it didn’t work.
Your siding,MSK would work but it would not give optimal results. The dig is that you may not need optimal results.
The elements of a tv antenna are cut to a precise length which corresponds to the wavelength of the channels carrier frequency.The longest element is a blocking element which blocks signal from coming in on the backside of the antenna. So you don’t recieve two stations.From then down to the front of the antenna they are precisely cut for each frequency or in the case of smaller antennas, group of frequencies.
The longest element is for channel 2
Oh a
They are aluminum
Quoth justwannano:
From my handy copy of Handbook of Chemistry and Physics, 56[sup]th[/sup] Edition, page E-84, “Properties of Metals as Conductors”
(numerous other metals and properties deleted for brevity)
Note that gold’s resistivity is higher than that of silver or copper, and almost as high as aluminum. This means that its conductivity is lower, and it’s thus a worse conductor. The reason that it’s used so extensively is because it’s very resistant to corrosion, and thus lasts longer, but uncorroded silver is much better.
From Basic mathematics for Electronics
"the Cooke Book
Specific Resistances at 20Deg C
ALum…17
bismuth…663.
copper drawn…10.4
German Silver…200 to 290
GOLD…14.7
Iron…448to 588
lead…132
mercury…565
nicrome…600 to 660
nickel…47
prospher bronze…23.7
steel…95 to 308
specific resistance of a wire is the resistance of 1 mil-foot of that wire.
Note aluminum is 17 gold 14.7 I don’t know how copper became so low but the reason we used gold was it’s conductability.
Hmmm
It appears that I have shot myself in the foot.
My college physics book says that german silver is an alloy
It lists silver at 9.7
Wow I can’t believe I forgot this.
Certainly one of the most important inventions to come out of ww2 I believe.
The Coathanga.