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Master Antenna Systems
for
Homes,
Businesses,
and
Communities
Just when you thought that old roof antenna was totally us eless, now comes technology that will make it more beneficial than your local Cable TV. You see, the ‘house antenna’, also known as the ‘Off-Air Antenna’ the ‘Master Antenna’, the ‘Local Antenna’, etc., now has a new life. Today new ‘digital compatible’ antennas are installed by ASTROvision Technologies as a professionally performing system.
HDTV is here now!
ASTec Installs and
Services, UHF, VHF, HDTV, Satellite TV, Short Wave, HAM, CB, AM, and FM
Antennas! Performance is our game!
MATV Systems
‘MATV’ means Master Antenna Television (system). A commercial MATV system is an expanded version of the multi-set reception systems
used in home antennas. It is used to distribute the signals from one antenna, or antenna array, to a number of wall outlets located at convenient points within a business unit. The antenna signals are fed through coaxial cable to a distribution amplifier. When multiple antennas are utilized, these signals usually pass directly to electronics of one type or another, commonly known as ‘processors’, in order to provide the best quality picture available. The amplifier increase s the strength of the signals and then splits them into two or more outputs. The signals of these signals are fed through coaxial cable to conveniently located splitters. The splitters, in turn, divide the main branches into sub-branches, which feed the wall outlets within the rooms. Properly sized coaxial cable is used throughout the system in, ideally, a ‘home run’ fashion. A properly installed system may be capable of carrying closed circuit TV (CCTV) or electronic bulletin board information.
A couple of new items have been added to those original free network UHF and VHF channels as well as local FM stereo music. Now, in addition you may receive:
- WEBTOP Broadcasting! Available with Microsoft Windows 98 and a TV tuner card in your PC.
- HDTV! The new digital TV channels are already available via that new roof antenna before they are shared with Cable TV. Besides, except for a handful of channels, Cable TV won't even provide the stereo!
- Independent stations providing local programming that may not be
available through paid satellite services.
- Best of all, these are available for free with a professionally installed, digital ready, quality antenna system.
How is that for technology? Be sure your ‘backbone’ distribution system is up to par. It's called the "backbone’ due to the fact it is the main artery that feeds and supports all your audio, video, entertainment, and data, usually on one price of quality coaxial cable. Our whole property wiring will provide compatibility and flexibility of technologies for years to come.
Basic Antenna Types
TV Antennas can be grouped in five major functional categories: VHF only, VHF/FM, UHF/HDTV only, UHF/HDTV/VHF/FM, and FM only combinations.
VHF and FM Antennas
Most VHF (Very High Frequency) antennas are engineered to receive TV channels 2 through 13. They also will receive the FM band, which is located between T V channels 6 and 7. FM only antennas are available also. Channels 2 through 6 are known as the low band. Channels 7 through 13 are referred to as the high band. Some VHF antennas are designed to receive only one band, either the low or high band. Antennas designed to receive both the low end and the high band are called VHF/FM broadband antennas.
TV channel 1 "disappeared" in the early days of TV because of a change in frequency assignments by the
Federal Communications Commission (FCC). A reshuffling of FM, Amateur, and other bands removed TV from the frequencies previously reserved for TV channel 1. Because the other 12 TV channels were already numbered 2 through 13, the channel 1 designation simply was dropped.
UHF/HDTV TV antennas come in a wider variety of shapes and sizes than do VHF/FM antennas. The wider variety of UHF/HDTV designs is possible because they do not require the long elements that VHF/FM antennas do.
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Combination UHF/HDTV/VHF/FM Antennas
Combination UHF/HDTV/VHF/FM TV antennas are designed to receive both the UHF/HDTV and the VHF/FM bands. Although the use of separate antennas for each band is ideal for peak reception (commonly used on commercial properties), new high performing UHF/HDTV/VHF/FM combination models are readily available and are becoming increasingly more popular.
To learn more about HDTV reception please see our:
Antenna Gain
The gain of the antenna indicates the relative strength of signal it can deliver to a receiver (TV, FM tuner, or commercial equipment). Most manufacturers list the gain of their antennas in decibels (abbreviated "dB"). The higher the antenna gain, the stronger the signal at the antenna output, and the more directive it will be to eliminate unwanted distant channels or interference from other than the specific channel the antenna is focused on.
How to Select the Right Antenna
There are many brands and hundreds of TV antenna models available. However, choosing the right one is relatively easy if you are aware of a few basic reception and TV antenna characteristics.
First, ‘good reception’, or production of a snow-free color TV picture, requires a signal level of about 1000 microvolts (uV), or 1 millivolt (mV), or 0dB, under ideal situations. Other factors that determine quality of performance, over signal strength, are carrier-to-noise ratios (C/N) which determine the noise-free picture. Noise is the direct result of random thermal and man-made generated noise that the signal must compete with. The signal must be strong enough to overcome the noise before a snow-free picture may result. C/N is the end result of a number of factors, beginning with the characteristics of the chosen antenna. By today’s standards, a signal strength of at least +5dB is necessary at the TV set, but strength alone does not produce the best picture to the viewer. Also, signals that are too high at the television set will damage the picture quality. To deliver the signal to the receiver, the antenna requires certain gain. The amount of gain required is dependent on the distance between the station’s transmitting antenna and the receiving antenna. The required type of antenna therefore depends on the channels to be received and the distance and direction of the customer’s site from the transmitting antennas.
These facts are readily available. Today, charts and other information will provide guidance in these areas. Be careful, for this information is useful under ideal situations only, which are under normal climatic conditions and true line-of-sight operation. Terrain is the biggest variable that will significantly impact ‘ideal’ line-of-sight data. In the ‘real world’ you need to take ‘real world’ measures, which in fact, would normally provide you with a sizeable cushion in gain and other performance characteristics. A professional installer, both knowledgeable and using digital signal level metering, can provide the assurance and best overall performance for a given budget.
It's
here! Are you ready?
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