Every year that I listened to FM radio or watched broadcast TV I noticed th at the radio signal fades if the antenna is not in its best direction or sh ape or length or something. I tried a hundred times during fifty years to c lip on a wire onto the antenna and that helps or hurts the reception. I dis covered that when I hold my hand near the antenna, reception is perfect, bu t when I go back to my chair, it fades into static.
I am the best antenna. No wire with alligator clips can provide the qualit ies that the human antenna provides. Here in my home in a deep valley, FM r adio is best when my foot is on the insulated wire antenna. Maybe I can get a water balloon shaped like me and put it on the antenna to duplicate my h uman talent with a mechanical fluid replacement. Then I can go to my easy c hair to listen.
Why is a human antenna better than a ten foot wire antenna?
When the signal fades, ambient reflections have created a null at the antenna's location (and a peak about a half wavelength away in some direction). When you walk over to it, you reflect some of the interfering wave (or absorb it).
So, there is a sense in which it is true, that a human is a better antenna than a hunk of wire. Bigger antennas are better, and -- having applied suitable Mexican-Hat-Dance and flailing-of-appendages procedures in the immediate vicinity of the antenna -- you're likely to find one configuration that works better (if not necessarily the same one, for every frequency/band and source of fading, however).
It's the electromagnetic equivalent of sitting around a campfire, having the smoke drift towards your face, and doing something superstitious to make it go away. Which invariably works, because ground-level wind is very random. But with the added trickery that, yes, a nearby body can actually make a difference.
I am the best antenna. No wire with alligator clips can provide the qualities that the human antenna provides. Here in my home in a deep valley, FM radio is best when my foot is on the insulated wire antenna. Maybe I can get a water balloon shaped like me and put it on the antenna to duplicate my human talent with a mechanical fluid replacement. Then I can go to my easy chair to listen.
Why is a human antenna better than a ten foot wire antenna?
You fall into the class of "Adaptive Self Tuning Antennas". If you could get someone else to help you, then you could be classified as an "Adaptive Self Tuning Antenna Array". Unfortunately, all self tuning systems require a feedback system with sensors, amplifiers, and actuators which leads to complexity and a requirement for input power. Batteries are expensive, generators are noisy and expensive, wires carrying power from the utility system can be tripped over and are unsightly.
The optimal solution seems to be, as you may soon discover, to train a compliant slave (or minion, if that is your preference) the art of optimal antenning and allow occasional refueling (pizza often works well) and bathroom breaks (said minion could provide feedback optimized refreshments and foot or neck smooshing as well).
There are various mechanisms for fading. My guess is you are experiencing "frequency selective fading" which is when you have two paths between the transmitter and your antenna. With a difference of
1/2 wavelength between the paths, they will cancel each other and your receiver will hear nothing. Move a little, and the length of one or both paths will change, causing the signal to return. The problem is common in urban canyons (building reflections) and mountainous areas (mountain reflections).
It's difficult to predict what adding a random antenna length to a receiver will do. A bigger antenna does not necessarily produce a better antenna. You could be detuning whatever antenna is provided by the manufacturer. Difficult to say without equipment and location details.
Bingo. There's your problem. Reflections off the valley walls.
You're about 70% water. Find a vinyl inflatable human body dummy and fill it with water. Attach to your receiver, and you'll probably have a usable antenna.
First, a 10ft wire antenna at TV/FM frequencies looks more like an inductor, which blocks RF, than any kind of antenna. What you're doing when touching the antenna is adjusting the relative levels of the various reflections that are canceling when they arrive at your receiver. You're not increasing the signal, but rather removing the interfering reflections.
I live in the San Lorenzo Valley, which probably has similar problems to your valley. In the distant past, when OTA (over the air) broadcasting was more common than satellite and cable TV, I designed TV/FM antennas with various amplifiers in the antenna. Most were attached to rotators to aim the antenna. In almost all cases, the strongest and best looking signals were not in the same direction and often not in the direction of the transmitter. I could literally tune the quality of the TV picture by rotating the antenna to point to a seemingly arbitrary direction. That's because the reflection was stronger than the incident (direct) signal. In the past, one could actually see the reflections in the form of "ghosts" on the TV picture, but not with digital TV.
I suggest you plan on installing a large broadband yagi TV antenna on your roof, along with a suitable rotator. Make sure you get an antenna mounted amplifier and good quality RG-6/u coax cable. Go to: and create a map and list of stations that you might possibly receive at your location. If there are no stations listed, give up, or get a taller tower. If that doesn't help, subscribe to satellite or cable TV, Netflix, Pandora, Hulu, etc.
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Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Considering the typos... are you already on the nightly "sauce" ?>:-} ...Jim Thompson
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I'll add if that's true, and Jeff is correct at 70% water, that would make him 3% human. Apparently some disagree with the 10%/90% and think it's closer to 42% human, 58% bacteria.
While we are on bacteria, you can have your gut bacteria analyzed for the cause of science. Dr. Rob Knight has a crowd funded project to collect bacteria from a wide range of people and analyze it hopefully see how different bacteria affect peoples health. Crowd funded in that you pay for the bacteria sampling kit they analyze and send you a report of your types of bacteria.
Oh, not drinking yet, I did have a little pomegranate juice mixed with grapefruit juice.
A finger acts like about 1k + 100pF from a node to "space".
Ferrite, of course, is best placed near a voltage node (current antinode). But its dielectric properties (mediocre volume resistivity, relatively high K) will still help against electric fields, if not as well.
For electric fields, try black antistatic foam. The stuff with fairly high conductivity.
There's also a metallized foam product (and various kinds of fabrics and fabric-wrapped-foam shapes), but it's very conductive so would tend to reflect rather than absorb.
If you shop around, you can probably find the stuff they line test chambers with. Not the tiles, I mean the foam pyramids. Some sort of radar-absorbent stuff. A few strips of that inside a shield box should do wonders.
that the radio signal fades if the antenna is not in its best direction or shape or length or something. I tried a hundred times during fifty years t o clip on a wire onto the antenna and that helps or hurts the reception. I discovered that when I hold my hand near the antenna, reception is perfect, but when I go back to my chair, it fades into static.
lities that the human antenna provides. Here in my home in a deep valley, F M radio is best when my foot is on the insulated wire antenna. Maybe I can get a water balloon shaped like me and put it on the antenna to duplicate m y human talent with a mechanical fluid replacement. Then I can go to my eas y chair to listen.
You could stick a hot dog or vienna sausage on the circuit. I suspect keeping the rest of the body attached is important. (And it's hard to fit a whole body inside your typical electronics box. :^)
When I buy a robot, it will need to pass my antenna test. It could adapt using audio feedback and it might have 70% water ballast. For now, a butler will be planned for his help with FM radio reception.
20,000 lbs of starch. At about $0.40/lb, that's $8,000 in potatos.
Are those two plastic antennas sticking out of potato man's head?
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Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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