![]() ![]() And these are low-noise amplifiers, with noise figure specifications less than 2 dB.Īt first glance, 30 dB appears to be a substantial signal boost! But if you are running a long cable from an outside antenna and splitting the TV signals two or three times, you’ll need that extra headroom to stay above the 20 dB S/N target we mentioned earlier. On two Amplify models, you can select between 17 dB and 30 dB gain simply by flipping a switch. ![]() Gain figures for the Titan and Amplify series of preamplifiers start at 16 dB and go all the way to 30 dB. You’ll need a high-gain preamplifier that can be mounted outdoors as close to the antenna as possible. And, you want to keep the system noise figure as low as possible. Here, the goal is to boost signal levels from all stations to provide more reliable reception. Again these amplifiers are intended specifically for indoor use to feed multiple TVs and set-top boxes.Įxurban and fringe areas require a different solution. For indoor antennas that need a little signal boost to overcome signal attenuation, the inline MicroAmp provides 10 dB of amplification in a super-compact housing not much bigger than a connector. This type of amplifier is typically mounted inside and won’t have the low noise performance of a mast-mounted amplifier, but a tiny bit of added noise isn’t going to cause you any reception problems when splitting strong local signals.Ĭhannel Master’s Ultra Mini-series fit this requirement nicely as they combine splitting and signal amplification in one convenient package, providing one, two, four, or eight amplified outputs. If you live in a suburban area with good signal levels and want to split the antenna connection to 3 or more televisions or set-top boxes, you’ll want a medium-gain distribution amplifier ahead of the splitter. Choose carefully!Īmplifiers for TV reception fall into two categories. But too much gain from an amplifier can boost already strong signals to the point where they overload the TV receiver, creating distortions and unwanted interference. That is they can receive both very weak signals and very strong signals reliably at the same time from channel 2 (VHF) to channel 36 (UHF). The trick is to achieve enough signal amplification without overdriving the TV receiver.ĪTSC receivers in televisions are designed with a relatively wide dynamic range. And you’ll want to use an amplifier that has a low noise figure, i.e., one that adds a minimal amount of noise while amplifying signals. If you are trying to receive weaker signals and run them through a splitter, you’ll need an amplifier to overcome the signal attenuation. The signal-to-noise ratio also decreases with longer lengths of cable.Īnd that’s where amplifiers come in. Signal levels are also reduced by attenuation in the coaxial cable running from the antenna to your television - the longer the cable run, the greater the attenuation. That won’t be a problem with strong signals, but it might make receiving weaker signals a real challenge. If the connection from your TV antenna goes through a splitter, the signal level drops at each splitter output. In reality with signal reflections and echoes (the so-called Rayleigh reception environment), that number can be 20 dB S/N or higher. The ATSC 1.0 digital TV standard defines that threshold is 15.3 decibels (dB) stronger than the noise floor - at least in an ideal environment. The best antenna system requires no amplification at all! In such a system, signals from TV stations are all above the required signal-to-noise (S/N) threshold for reliable reception. ![]() Depending on the location of the amplifier in the signal chain, noise can become a significant problem for reliable reception of weak signals. And amplifiers also create noise of their own, like any other active electronic circuits. But as a rule, amplifiers don’t discriminate: Without special filtering, any signals coming into an amplifier, including unwanted ones, are all boosted. There are good amplifier designs and cheap amplifier designs, and you get what you pay for.Īmplifiers ingest weak TV signals and make them stronger. Amplifiers can do a lot of good, but they can also create problems for TV reception. Everyone knows what an amplifier is, but there’s plenty of misunderstanding about how TV amplifiers work and when to use them. For this month’s post, we’re going to focus on TV antenna amplifiers. ![]()
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