TV Antenna Preamplifiers|
A TV antenna preamplifier is a small amplifying device that is mounted on the mast or antenna boom as close to the antenna output terminals as possible, so that the strength of a very weak signal is increased (amplified) before it enters the transmission line (coaxial cable) going from the antenna to the TV sets. Without this preamplification, the strength of the already weak signal (0 dBmV or less) would be further reduced as it passes through the transmission line producing "snow" on the TV screen.
By adding an outdoor antenna preamplifier to your antenna system, you can effectively boost available antenna signals often weakened by long coaxial cable runs or multiple television sets. A preamplifier can also be used to improve incoming signals from distant VHF/UHF and FM stations. In areas of very weak signal, you may need to use a preamplifier initially to increase the signal levels to a distributable level. No matter where you live, there is a Channel Master preamplifier to solve your specific reception problem.
Even if you are in a good reception area you may be having problems providing good signal to a number of sets. Preamplifiers by Channel Master can mean the difference between snowy so-so images and sparkling, true to life, crystal clear pictures. Channel Master preamplifiers will also control potential interference from strong FM radio signals.
The TV Antenna preamplifier is most useful to persons unable to view channels due to weak signals. The preamplifier will boost the signal received by the antenna, making it much stronger by the time it reaches your TV set. It also helps to maintain the strength of the signal as it travels through coaxial cable. Signals received by your TV antenna become weaker as they travel through coax cable and the longer the journey, the weaker the signal becomes.
If your local broadcast stations are not transmitting strong signals, or you don’t live near the broadcast stations, a preamplifier is almost a necessity if you want to receive a clear signal by the time it reaches your television.
If you have more than one TV outlet, you will need to use a signal splitter. However, with the use of splitters, the signal becomes weaker. This problem increases as the number of splitter outputs increases. Both weak signals from the broadcast station and the insertion loss of splitters and coaxial cable can be overcome by installing a high quality Channel Master TV antenna preamplifier (Spartan 3 CM-0068DSB, Titan 2 CM-7777, and Titan 2 CM-7778), which will amplify the signal at the source before the signal loss occurs.
Channel Master preamplifier units consist of an amplifier housing unit which is mounted on the antenna mast and a power supply which is installed indoors. This power supply unit is connected to the outdoor unit via coaxial cable, which powers the outdoor booster. The connection between these two units acts as a two way stream, providing voltage to the booster while passing through digital signals to the in-house distribution system.
The outdoor antenna amplifier unit is easily mounted on either the antenna or mast. Weather boots and connectors are provided with all models. The amplifier housing cover is equipped with self-retaining screws that can't drop out and get lost when the cover is removed during installation. All units are designed for fast, easy installation.
The Channel Master preamplifier line displays the same superior engineering and technology that has made Channel Master the largest manufacturer of television and FM reception equipment in the world. The heart of any television antenna system is its amplifier. Channel Master makes a full line of amplifiers, which have won Channel Master a reputation for quality, reliability and superior performance with knowledgeable engineers and installers across the country. Channel Master builds that same quality, reliability and superior performance into every preamplifier in the line.
If you already have an antenna set up and are considering adding a preamplifier to boost your signal strength, you would only need two additional short length coaxial runs, one from the antenna output to the preamplifier input (which should be no more than 5 feet) and one from the indoor power-supply to your TV set. You would simply use the current longer coaxial run to connect from the mast mounted unit’s output to the indoor unit’s input.
Channel Master preamplifiers provide extremely high gain and low noise for deep fringe reception. Channel Master preamplifiers allow you to receive programs on distant channels broadcast from longer distances. They have a high signal level input capability to prevent extremely high level TV signals from causing an overload. The most common problem of all is VHF reception in the deepest fringe areas. No local interference problem, just a lot of snow in the picture, or the HDTV digital channels will lock up and “tile” (the picture separates into small blocks). These units offer the highest gain and the lowest noise figure (electronic "noise" is what causes snow or digital tiling) of any home amplifier on the market.
HIGH GAIN, LOW NOISE
When an antenna delivers a weak signal, ambient and electrical noise cause snow to appear in the TV picture. HDTV and digital channels will lock up and “tile” (the picture separates into small blocks) when the signals are weak. Preamplifiers provide an ideal solution to this problem. The first job of an amplifier is to provide even, distortion-free gain while maintaining a low noise figure. This is especially true in antenna mounted amplifiers where the central problem is most often a poor signal to noise ratio. Advanced circuitry and design provides the preamplifiers with the high gain and low noise needed for extraordinary, crystal clear, quality reception.
EXTREMELY HIGH INPUT CAPABILITY
Often both distant and local TV stations are amplified in order to improve the reception of the distant channels. The amplification of the strong local signals can cause an overload condition in some amplifiers. This results in a degradation of picture quality, which can manifest itself in a variety of ways. Signal overload and cross modulation are greatly limited by the improved input capability.
SUPERIOR LIGHTNING PROTECTION
Ambient electrical discharges during electrical storms are the single greatest cause of antenna mounted amplifier failure. Channel Master preamplifiers have survived lightning discharge voltage tests. This exceptional degree of lightning protection is the result of several factors. The layout and design of the circuit boards and the correct spacing of conductor paths and components combine to prevent static charges from arcing through the circuit. Twin diode energy absorption circuits block the flow of static energy at the output as well as the input terminals so that the preamps are protected from power surges up the line as well as down.
Channel Mater outdoor amplifiers can operate under the worst imaginable weather conditions. Special feedback circuitry assures operational stability at temperatures ranging from -22°F to 140°F. Despite the most radical changes in temperature and moisture, despite fluctuations in line voltage, Channel Master antenna preamplifiers provide constant, flat gain with no oscillation or hum.
When to Use a Preamplifier
There is no simple or universal rule that tells you when to install an antenna-mounted preamplifier. Generally, if the level of the received signal is less than 0 dBmV at the receiver input terminals, preamplification is needed.
Customer preference is another factor that must be weighed when considering the use of a preamplifier. Some customers may not agree to the added expense of a preamplifier and will be content with a picture that is less than perfect. Others may insist on a preamplifier just because they want only the best.
Installing a Preamplifier
A preamplifier consists of two units: the preamplifier itself and a power supply. The preamplifier is mounted on the antenna boom or on the mast as close to the antenna as possible. The power supply unit is mounted indoors. Power is supplied to the preamplifier unit through the transmission line.
The preamplifier is located as close as possible to the antenna feed point because the weak received signal must be amplified before it loses signal going through the coaxial cable, and also before it can be subjected to interference from sources between the antenna and the receiver. Preamplifiers mounted farther from the antenna usually amplify (magnify) the interference along with the signal.