- Posts
Development comes before invention. A project description comes before development.
Development comes before invention. A project description comes before development.
In another forum we are trying to invent practical methods of establishing legal grounding in very limited environments.
In this forum I am disclosing the description for an entirely different invention.
Part of our problem on medium wave is the mismatch between wave-length and legal antenna length (3-meters). Everything else, including good grounding, is an attempt to maximize the result.
We are able to multiply and divide frequencies (wavelengths), amplify and attenuate them, so why can’t we shorten them without changing pitch?
In digital audio it is possible to change pitch without changing time length, and it is possible to change time length without changing pitch.
So why not invent a thing that will make a medium wave length short without changing its pitch (frequency)?
I ask you.
Total posts : 45366We’re stuck with the wavelengths which radiate since this is given by (wavelength)=(speed of light)/(frequency). In a vacuum or air the speed of light is essentially constant.
But, in a conductor the speed of light is slower than in air so the wavelengths are shorter. In a coax where the speed of light is 2/3 that in free space the wavelengths are proportionally shorter.
This is also true under water. Maybe we should install our antennas under water.
If I understand digital warping it is done by adding duplicate or dropping chips of the audio waveform. Maybe something similar can be developed for RF. More thought is needed for me to grasp this.
Neil
Total posts : 45366“If I understand digital warping it is done by adding duplicate or dropping chips of the audio waveform. Maybe something similar can be developed for RF.”
That is correct. Adding and taking away bits of samples and then placing those sampled samples and inserting them before or after the master sampled bit, either once or many times over the normal wavelength’s time domain.
It probably could be done for RF, however I doubt a receiver would be able to properly receive it unless said receiver had digital decoding circuitry. We don’t want our RF waveform after detection to stretch or shorten the content on it (modulation) and the receiver would also have to re-construct the RF waveform internally so that the bits and pieces are arranged in proper order again before demodulating that waveform.
May be able to be done, but I doubt it would be a simple task, at least not without considerable timing and error correction. Probably end up with the same thing like digital TV, a 1 or a 0…meaning a picture or no picture or a very lagged and high dropout or freeze issues.
An interesting concept though.
RFB
Total posts : 45366I hope I spelled that right. I remember back in high school my physics teacher talked about some kind of perpetual motion machine that created its own energy. Your idea sounds as interesting as that.Lol But I have to agree with RFB. Either the signal wouldn’t be received right or you would be duplicating a digital type of signal on the analog bands. I’ve used digital TV and HD radio before. In fact, I was one of the people suckered into buying an HD radio that can’t even lock a digital FM signal while you’re driving. I’ve never tried HD AM, but from what I’ve heard it’s a disaster. Tons of hash on adjacent channels and weak signals. Also, digital TV is terrible when you need it. During severe weather it pixels out every time there’s lightning between here and Cincinnati.If there was a tornado coming our way we wouldn’t know it because the radar’s a puzzle of pixels. I apologize for rambling. I tend to drift off topic like a broken radio drifts off a frequency.
Total posts : 45366I need to go over to your opening post and say something, but I hope somebody gets there first to answer your very good questions. I am not certain about all those things.
Yes, this quest for a breakthrough in technology is, as you surmise, yet another attempt by a part 15er who feels constrained by the short antenna limit while AM radio works best with very long antennas. We need a magic pill to make the short antenna think it is a long antenna, and act like it.
Total posts : 45366… It would forever change radio. I would love to get out 10 or 15 miles on part 15 (which I assume would be possible if this ever happened). Of course the FCC would probably spoil it with a new, shorter antenna length maximum.
Total posts : 45366Without wanting to do any harm, we need a Tesla Frequency Twister which phases out the FCC brain and makes them want lunch above anything on earth.
During this never-ending lunch we squeeze in as much part 15 broadcasting as the world can withstand.
Total posts : 45366…to get 15 or 20 miles out of part 15? I keep thinking about your idea. It’s the best idea since sliced bread. We need to figure out a way to slice this theoretical loaf of bread. There’s gotta be a way.
I know this sounds like a dumb question (I’m new to radio), but would burying radials or grounding rods deeper in the ground be legal or improve range? The FCC can’t see what’s underground. All they would see is the legal 3 meter setup above ground, not the 5 meters underground.
Total posts : 45366Channel X 1610AM has brought a super question to the discussion.
On various threads, if I understand what’s been said, we have concluded that horizontal radials do NOT radiate, whether they are above or below ground, but they DO provide the “ground return” needed to cause the signal to travel the farthest distance.
However, and here’s where this new question begins to have importance, I think it was Radio8Z who explained that SLOPED ground radials, whether up on a roof or otherwise sloped downward toward the earth, DO add radiation because the various sloping elements are at DIFFERENT angles from one-another and DO NOT cancel out. We found that sloped radials would therefore probably NOT meet approval.
HOWEVER, if the sloping radials are underneath the ground, could their benefit be enjoyed in their undetectable, buried location?
One drawback would be the extensive digging required to achieve such a radial installation.
BRAIN ACTION — What about having BOTH types of buried radials? Horizontal AND sloped?
Total posts : 45366This sounds very out of the box, but what about burying a vertical set of radials underground? It would require a tedious amount of digging, but you would theoretically have a grid of metal acting as a huge underground antenna, which would not be detectable by the FCC.
Total posts : 45366The radials are connected to transmitter ground, so if you arranged them vertically, you would cancel out the vertical antenna output and reduce your overall signal almost completely.
The antenna output and ground outputs are at opposite polarity.
Total posts : 45366channelx1610 wrote:
“to get 15 or 20 miles out of part 15? I keep thinking about your idea. … There’s gotta be a way.”That would be nice, but a typical Part 15 AM system on 1700 kHz even with a zero-loss ground connection to a perfect ground plane would produce a useful, but not noise-free signal at a distance of about 1 mile. So that is pretty much the upper limit.
Greater range is possible for elevated systems where most of the radiation is produced by a long “ground” conductor (see link below). But those systems are not functionally compliant with Part 15.219(b).
http://i62.photobucket.com/albums/h85/rfry-100/AM_System_Comparison-1.gif
Total posts : 45366It sounds like sloped radials buried underground is the best idea. I think someone needs to try this idea and see what happens. If I had the funding and a studio/transmitter location (I still live with my parents), I’d do it. It sounds like an interesting experiment.
I just thought of another idea. An extremely long (maybe 20 foot?) grounding rod (not a radial system) hammered in the ground. Wouldn’t that radiate better than buried radials? Again, I’m new to radio, so that idea could be smart or incredibly stupid.
The reason I mentioned such a great distance was if Carl’s idea to somehow make a typical part 15 setup act like it has a longer antenna system, a greater range could be achieved. I’ll admit even getting out 10 miles would be hard to do, even if Carl’s idea existed. It would mean making the transmitter think it’s on a professional tower, which boggles my mind.
Total posts : 45366The heading of this thread is “Invention”. I would suggest that “Rich” review the concept of invention.
His bring-downs seem very authoritarian, pulling us always back to a world where imagination is folly.
Total posts : 45366Developing and exploring ideas has lead to many advancements in many areas, and IMO needs to be encouraged.
In the nature of exploring the idea of various forms of buried wires used with Part 15 AM systems, such experiments have been done in the broadcast industry over the years. They show that all of the useful radiation from these monopole antenna systems is produced by the conductor(s) above the surface of the earth.
The forms and physical locations of the buried conductors determine their loss while acting as a return path for the r-f current induced in the earth near the radiating antenna. That return path is required in order for r-f current to flow along the antenna itself — and it is the flow of r-f current along the antenna that produces the radiated signal.
So in that way, buried conductors are very important to the efficient operation of the antenna system, even though they produce no useful radiation themselves.
Hopefully this info will save some research and experiment time as far as this subject goes, and is not too discouraging to anyone.
- You must be logged in to reply to this topic.
