Long ago there lived a race of cat people who had much the same problems with antennas that we humans have today: bad reception during the last few seconds of a game, continual snow during their favorite part of their favorite movie, and a severe lack of the "magic position" that one is required to hold when covered in tin foil and grasping the antenna. Unfortunately for them, they did not have this web page to reference and therefore they died. This left an opening for humans. Initially, humans could only communicate verbally over short distances, yelling distance that is, stirring in them a desire for long distance communication (very different from a long distance relationship, do not get the two confused, otherwise this site will make absolutely no sense). Okay, so I made that part about the cats up, but seriously, if anyone knows how to get good reception with a younger brother covered in tin foil, let me know......not that I have done it, mind you, I am just wondering. Now, on with the show.
The first antenna experiments were conducted by Joseph Henry in 1842 at Princeton University. Henry was successful at "throwing a spark," when he observed that magnetic needles were magnetized by a current induced in a circuit several floors up. In 1885, Thomas Edison patented a communication system the used a type of vertical antenna. Then came James Clerk Maxwell, who in 1864, presented his theory on electromagnetism to the Royal Society, providing the theoretical foundation for antennas. With this discovery, many other scientists began to explore this new frontier and the age of the radio began.
Just so you do not end up like this guy, I am going to explain a few terms so the technical discussion is a little easier to follow. (Note: do not actually try to open a window in such a manner, you will most likely throw your shoulder out because mice have relatively low mass and it takes a heck of an arm to get them up to window cracking speed, aka "ludicrous speed" for you Space Balls fans). The terminology is as follows:
Technical Stuff
Here is the information that goes a little deeper into the theory of how an antenna works. Although this is not a very intellectually intense site, I will warn those viewers on a lunch break or perhaps surfing the net while "between projects," that there are some concepts on this page that use what some people call "math," and other supposedly important "scientific information.
wireless communication got a lot of attention when a message was transmitted that allowed for
Radio waves were first discovered in 1887, but radio itself was initially invented by Italian Guglielmo Marconi in 1895 (1). His biggest mentioned success was in 1901, when he managed to broadcast the letter “S” across the Atlantic Ocean (1). However, he focused primarily on point-to-point transmissions, not large scale broadcasts from one point (F). As such, three American inventors - Lee De Forest, Edwin Howard Armstrong, and David Sarnoff - took credit for making radio as it is today a success (F). De Forest was born and raised in Alabama and he thought of everything in terms of patents and eventually held more than 300, but many claimed that he simply stole the inventions of others (2). In 1900, he patented a device to enhance weak signals and in 1902, he formed the De Forest Wireless Telegraph Company (1). In the same year. Reginald Fessenden, a Canadian, invented the “electrolytic detector”, which later became the spade detector that brought De Forest so much fame (F). In 1904, John Fleming invented the oscillation valve, which later became De Forest’s audion, and De Forest won the gold medal at the St. Louis World’s Fair for his “spade detector” (F). De Forest gained quite a bit of fame by broadcasting music live from the Eiffel Tower and from the Metropolitan Opera; however, many believed that this was a scam and that he had actually had the device broadcasting the signal only a few blocks away (F). In 1906, he envisioned bringing music and voices to all American households, but as it turns out Canadian inventor Fessenden had already broadcasted a Christmas greeting and music to the crew of a ship off the coast of Canada on Christmas Eve a year earlier (F). In 1912, Armstrong became prominent by inventing regeneration, wh...
Ewald Georg von Kleist is a German scientist who created the capacitor in November of 1745. Regrettably, Kleist did not have the proper paper work to claim in the records that the design of the capacitor was his idea. Many months later, a Dutch professor named Pieter van Musschenbroek created the Leyden jar, the world’s first capacitor (on record). It was a simple jar that was half filled with water and metal above it. A metal wire was connected to it and that wire released charges. Benjamin Franklin created his own version of the Leyden jar, the flat capacitor. This was the same experiment for the more part, but it had a flat piece of glass inside of the jar. Michael Faraday was the first scientist to apply this concept to transport electric power over a large distance. Faraday created the unit of measurement for a capacitor, called Farad.
The electromagnetic spectrum is a range of different types of radiations, this is energy that travels and spreads out as it goes. This range involves more than just visible light- small portion of the spectrum detected by the human eye- it goes beyond what the human eye cannot see. The two most important characteristics of the spectrum are wavelength and frequency. The electromagnetic spectrum can be divided into three different parts: the theory of visible light, the range of the electromagnetic spectrum, and how it benefits mankind.
In 1751, Franklin published some his theories on electricity. Franklin had an attraction to electricity and invented the Franklin Stove, and coordinated the kite-and-key experiment. Franklin’s most famous experiment was when he flew a kite in a thunderstorm to prove that lighting is an electrical power. Franklin continued to pursue his interests in invention by inventing the lighting rod, swim fins, bifocals, and musical instruments.
Rogers Communication started with a vision that "radio is an electric pipeline" by Edward S. Rogers, Sr. In 1925 Mr. Rogers, Sr. invented the world's first alternating "current (AC) radio tube."1 The radio tube was a huge break through in communication technology and in radio reception, and as a result of the invention; radios became common medium of communication.
Usually, when people think about the inventor and founder radio, people tend to say it was Guillermo Marconi. However, after watching this documentary, I believe the inventor and founder of radio has to be the combination of the three men profiled in this documentary; Lee De Forest, Edward Howard Armstrong, and David Sarnoff. Lee De Forest is also sometimes considered the Father of Radio, and even the Grandfather of Television, however, there was always a lot of controversy over his work. Under multiple circumstances, his inventions and discoverers were previously discovered by other inventors earlier in time, leading to multiple lawsuits. Even though there was a lot of controversy over his ideas, he did however come up with one of the
In 1837 Morse got two partners to help him develop his telegraph. One was Leonard Gale, a quiet professor of science at New York University who taught him how to increase voltage by increasing the number of turns around the electromagnet. The other was Alfred ...
By 1920, radio circled the globe and the first radio transmitter was developed and broadcasted programs for the public. Later, the idea of the radio was adopted by television, radar and communication systems, due to the advancement in electronics equipment and enabled radio waves to be sent over greater
When a ray of light is bounced or reflected off of a plane surface, there is a specific law that can be used to predict the angle at which it is reflected off of the surface. This is known as the ‘Law of Reflection’ and it states:
The first stage is the RF amplifier. The AM antenna runs into the RF amp where the desired frequency is selected. As stated by Grob (1997), the typical band for AM is 535 Hz to 1605 KHz. For the duration of the paper, we will assume that we are trying to receive a station that is located on 1290 KHz signal. The antenna used must be able to pick up all the stations on the AM dial. Knowing this, we need to select the one we want to hear. In this case, we want 1290 KHz or The Country KOWW. When the dial on the radio is turned to select 1290 KHz, it does two things. There are two variable capacitors
Every invention ever known to man had pioneers or people who contributed to the creation of the product. Radio had many pioneers that allowed for its creation and their names are Heinrich Hertz, Nikola Tesla, Ernst Alexander, Edwin Armstrong, Guglielmo Marconi, Lee DeForest, Frank Conrad, Reginald Fessenden, and Edward Armstrong. It all started with a German physicist named Heinrich Hertz who in 1884 proved that you could transmit and receive electric waves wirelessly. Hertz thought that the work he had done had no use whatsoever but little did he know that what he done is considered the fundamental building block of radio, and that is the reason why every frequency measurement is named after him (Short). In that same year a Serbian-American inventor named Nikola Tesla came to the U.S and sold patents to his inventions to a man named George Westinghouse. After that Tesla established his own lab which is where he built the tesla coil , an induction coil that is still used in radio today (Short). The next progression of radio focused on more than just the transmission of waves, the new focus was transmission of speech. The first to begin to add speech into the radio mix was Ernst Alexander, a Sweden born inventor who developed the first alternator to make speech transmission possible (Short). This was so new to the s...
Radar can be traced back as far as 1832 when British physicist Michael Faraday suggested the existence of an electromagnetic field between certain objects from his scientific observations. Working from these ideas, British physicist James Clerk Maxwell predicted mathematically the existence and behavior of radio waves in 1873. In 1886, physicist Heinrich Hertz from Germany and Elihu Thomson from America confirmed the existence of radio waves with demonstrations showing examples of reflection, refraction, and direction finding of radio waves. By 1904, Christian Hulsmeyer, a German inventor, applied for a patent for a device that used radio waves in a collision-avoidance device for ships.
The research that established Faraday as the foremost experimental scientist of his day was, however, in the fields of electricity and magnetism. In 1821 he plotted the magnetic field around a conductor carrying an electric current; the existence of the magnetic field had first been observed by the Danish physicist Hans Christian Oersted in 1819.
Scientists and engineers have been able to enhance our lifestyles by understanding and using the Laws, Concepts and Principles of Optics and how they are applied in Optical Instruments. The key concepts are: