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ANTENTOP-02-2003

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Tesla described his wireless power transmission method by three characteristics: 1) the reduction or elimination of electromagnetic radiations, 2) that it operated through the earth, and 3) that the mechanism of transmission is an electric current - as contrasted with radiations. Modern analysts, on the other hand, model Tesla's transmission system on present day broadcast radio technology. This model assumes an antenna propagating electromagnetic waves into the air where these radiations either will not or will, depending on the presuppositions of the writer, bring about the effects claimed by the inventor.

One of the possible causes of interferences to reception of the radio and television from Power Amplifiers (PA) is degradation of an output tube or an output transistor of the Power Amplifier (PA).

Back to 90th, it happened, that my power PA begun to produce TVI and very heavy TVI were appeared only on 40 meters. A low frequency filter that was installed on the PA had not given any effect. My researches showed me, that neighbours' TV-sets were overloaded by power signals leaking from my PA to wire of the main. Most power leaking was only on 40 meters. I did not know the reason for the damage till now, but I needed to remove the TVI. What could I do?

VHF Antennas and Equipment

Prepared by RK3ZK

Just a table

As usual, such towers are used for erecting VHF antennas of a service radio station, and Russia commercial firms widely make such Antenna Towers.

I think, hams also can use some ideas from construction of the tower for their operation. 73! Igor Grigorov, RK3ZK

Any amateur can do the antenna during one hour. To do the antenna takes a half of hour and to tune the antenna also takes a half of hour. So, do not waste time and go to make the Bottle Antenna!

Very good and very reliable VHF Antenna!

Most of us are heard about VHF antenna X200.It is very interesting and very reliable two bands antenna. RV9CX made some modifications for the antenna, so, the new RV9CX-X200 is more suitable for doing at amateur conditions. Go to the next page for the new antenna!

HF Antennas

After getting my first amateur license I had to think, what antenna to build for a top-band (160 m), I realized, that conditions are too bad for it. I live in a 7-floor house, which has a roof with a high slope (about 35-40 degrees), which is very dangerous to operate on it. Also, the house is almost completely surrounded by wide streets and electrical wires going along them. After long thinking, I concluded, that there is only one possibility to make an antenna - to hang up a long wire from my roof to the roof of another house.

For several years I use to a simple and rather effective home - made antenna for a work from my balcony, a hotel window, from the ground in a radio- expedition and from my car. I with my friends have made a dozen such antennas and all the antennas work very well. One antenna, in depend of its dimension, works at three old amateur ranges- 10, 15,20 or 15, 20,40, or 20,40, 80.

The antenna was made by me in one of the hot summer days near five years back. I was going for weekend to my bungalow and I decided to take my home- brew 80 - meters transceiver with myself. I had no antenna for the transceiver. So, I needed to do any antenna, but I had no time as no quality stuff for doing this one. I opened my box with old tips… and… Thirty minutes while I have had a new antenna that served me several years!

LF- 136 kHz

The power radiated by an antenna is equal to the radiation resistance multiplied by the antenna current squared. Measurement of antenna current can be done in the 137 kHz band by for instance a thermocouple ammeter or other means.A more reliable way of determining radiated power in the 137 kHz band is by measuring the field strength near the station but outside the near field region. A distance of 1 km is probably sufficient to reduce the influence of the near field on the measurement sufficiently and 2 km is definitely safe.

Just photos

QRP

Remember, '70-th when I was a young SWL, I has build my first direct conversional receiver. It was too wonderful for me because he is very simple, just a three transistors are in receiver's circuit and a few any details. I powered this RX by 9 volts battery of pocket broadcast receiver. I has not a good antenna and I used a piece of wire in my room. For the first testing construction I did not made a PCB and build this RX as "space" style on a piece of printed board. It was a 80m band version. Results was shocked me at once!

Gnomic 80-m QRP- Transeiver: by Oleg Borodin, RV3GM/QRP

The goal of this project is to provide to Amateur Radio beginners with a working QRPp CW transceiver that they build and learning the knowledge of transmitting and receiving equipment on the most of popular HF band 80 m.This "Gnomik " transceiver contains two separate units: direct conversion receiver (RX) based on modified DC receiver designed by Vlad Polyakov RA3AAE and transmission unit (PA) based on standard scheme frequency-doubler and amplifier. The RX's heterodyne operate on a half of receiving frequency.

"Micro-80" is the first smallest and the simplest transceiver in the World. This is a prototype of some next wellknow kits "PIXIE", "Tiny Tornado".

The day before yesterday I decided to hang my ZL-antenna for 20m in another direction - and so sad it was for me, fixing the last point I broke director wire. My antenna made of D6mm antenna-rope had been already used for 2 years and I had no any desire to prolong it's term

Techniques

I found one more useful application for AT-33T transformer. This one was turned to a current transform for an RF ammeter. You need to add only a current loop to AT-33T transformer and this one will be a current transformer for an RF ammeter.

Tesla's writings have many references to the use of his wireless power transmission technology as a directed energy weapon. These references are examined in their relationship to the Tunguska explosion of 1908 which may have been a test firing of Tesla's energy weapon.This article was first published in a different form in 1990. The idea of a Tesla directed energy weapon causing the Tunguska explosion was incorporated in a fictional biography (1994), by another writer, and was the subject of a Sightings television program segment.

Just one hundred years ago, J.C. Bose described to the Royal Institution in London his research carried out in Calcutta at millimeter wavelengths. He used waveguides, horn antennas, dielectric lenses, various polarizers and even semiconductors at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Calcutta. Some concepts from his original 1897 papers have been incorporated into a new 1.3-mm multi-beam receiver now in use on the NRAO 12 Meter Telescope.

A 100 years after Jagdish Chander Bose, India seems to have come to the painful realization that it is unlikely to make any worthwhile scientific inventions any more. It has therefore decided to invent a J.C. Bose that did not exist before. This Bose cannot be patented internationally but can certainly be put to good use in the domestic and NRI market. Bose is one of the founding fathers of radio-physics, whose research acted as a bridge between the original discovery by Heinrich Rudolf Hertz and practical use by Guglielmo Marconi.

Credit Line: http://top-biography.com/9049-J.%20C.%20Bose/spfeat.htm

Celebrity author Leo Tolstoy has remarked in his short story entitled The Exile: God sees the truth, but waits…. This is exactly what happened, in case of J. C. Bose. Today, the world knows Marconi, an Italian experimentalist, as the inventor of radio waves. But it was Bose, who first invented a device called Mercury Coherer, which could transmit and receive radio waves. It is used in mercury tube and telephone. One of Marconi's close friends, Luigi Solari, a lieutenant in the Italian Navy, drew Marconi's attention towards Bose's invention. He made minor changes in the devices, such as the U-tube was turned into straight tube. A device just a replica of the Bose's instrument was presented for a patent by Marconi, on September 9, 1901. He was credited by the world for sending the radio signals across the Atlantic Ocean, for the first time.