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Title: What is required to run a feed? Post by: dave on October 16, 2005, 08:50:44 AM - A receiver capable of picking up airband transmissions (118-136 MHz)
- An always-on Internet connection (feed uses a total of 16kbps) - streaming does not work well over dialup modem connections - streaming is possible over even the slowest DSL connection - 16kbps is barely noticeable and will not affect your connection - an external antenna (preferred for optimum reception) - audio cable to connect scanner to PC's sound card - typically 1/8" to 1/8" stereo cable with mono or stereo plugs - a PC running Windows 98/2000/XP, Linux, or Mac OS X - free open source software that we provide and help you set up Airband (118-136 MHz) is part of the VHF radio spectrum. It is very easy to pick up aircraft since the path from the aircraft to your receiver is almost always "line of sight." The challenge is picking up the controller end of the conversation. The controller end of the conversation comes from a ground-based transmitter which may not be located very close to your house. Typically, though, if you are within 10-20 miles of the transmitter and not located in a deep valley, you can pick them up. If you are more than 5 miles away it will almost always require some sort of outside (external) antenna. Many external antennas are available, from commercial antennas to antennas you can build yourself. Some antennas which work well are: Scantenna from Antennacraft: http://www.grove-ent.com/ANT7.html Grove Scanner Beam II: http://www.grove-ent.com/BEAMII.html This antenna is particularly useful if you are trying to receive controllers that are more than 10 miles away from your location. It won't pick up controllers 50 miles away, unless you are located on a tall hill, but it is useful for controllers in the 10-30 mile range. The terrain between you and the ground transmitter, plus your local power-line noise situation, play the largest roles in determining reception quality. Radio Shack: Cost-effective base scanner antenna: http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=20-176 Discone antenna: http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=20-043 The discone is highly recommended as a good overall scanning antenna, especially if you are going to use your installation for more than just airband reception. Discone antennas cover a wide range of frequencies. Homemade (sometimes called homebrew) antennas: Vertical dipole antenna: A dipole antenna is one of the most basic antennas. Many ham radio operators will recognize the dipole antenna as a staple of HF operation, but dipoles can be built and used for VHF as well. Here is one plan for a vertical dipole...as with any antenna, you will need to scale its dimensions for airband (118-136 MHz): http://www.alpharubicon.com/elect/vertdipoleniet.htm Note: None of these antennas, except for the discone, will cover the complete airband since it covers such a wide frequency range. When designing your antenna, pick a center frequency closest to the frequencies you will monitor most of the time. J-Pole: The so-called J-Pole antenna is an omnidirectional (non-directional) antenna that is cheap to build and very effective. It typically has about 2.5dB of gain over a dipole antenna. Many plans for building J-Pole antennas can be found here: http://www.dxzone.com/catalog/Antennas/J-Pole/index.shtml Quarter-wave (1/4-wave) Vertical: Though it provides unity gain (no gain), this antenna is simple to build and iinstall. It is sometimes called a "ground plane antenna." A good plan for building your own can be found here: http://www.hamuniverse.com/2metergp.html Decent guide to scanner antennas: http://www.fordyce.org/scanning/scanning_info/scanant.html[/i][/list] |