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Amplify a Digital TV Signal

Put A Little Electricity Back into Your Digital TV Signal

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If you use an antenna then by now you've probably noticed differences between analog and digital television - a wider screen, channel numbers with decimal points, use of a DTV converter box, and so on.

There is another difference, an invisible difference, that is the cause of lost or inconsistent reception and a new Federal Communications Commission (FCC) translator program.

It's the digital TV signal.

Analog v. Digital TV Signal

Given identical broadcast conditions, a digital TV signal won't travel as far as an analog TV signal because terrestrial constraints affect it more than analog. Things that affect reception include roofs, walls, hills, trees, wind, etc.

A digital signal is so sensitive that a person walking in front of it can knock it offline. In comparison, an analog signal is like a roach. It'll take more than someone walking in front of the antenna to drop the signal.

Moral of the story is that in order to receive a good over-the-air picture you need a good signal entering the TV tuner, whether it's located within the TV or digital converter box. The problem is that signal loss is a concern with digital TV.

In some circumstances, you can do everything right and still not get a signal. Or, you may experience too much signal loss while the digital TV signal travels from the antenna to the tuner.

Whatever the case, amplifying or boosting the signal is a potential fix to your reception issue.

Do You Need Amplification?

The key criteria for amplification is that you have an existing signal being received by the antenna. If the antenna has a signal then amplification could be a cure for intermittent signal loss. If it doesn't then amplification almost surely won't fix your problem.

Amplifying a Digital TV Signal

Amplification is a tricky concept. CEO of AllAmericanDirect.com, Mike Mountford, explained it best when he compared amplifying a digital TV signal to connecting a nozzle at the end of a hose to get better spraying power.

In his story, the antenna without amplification is like the hose with a light trickle coming out of the end. Alone, this trickle isn't very powerful when spraying, but since it's a trickle you can use a nozzle to increase water pressure by limiting the amount of water coming out of the end. The nozzle will feature a more powerful spray than without.

In this example the nozzle is the amplifier and water is the digital TV signal. The amplifier uses electricity to harness the TV signal and send it along it's way with an electrical boost. This allows the DTV signal to travel farther with more power, which should provide a consistent picture.

Amplification isn't a guaranteed fix for every poor TV reception scenario but it is an option. It also isn't a fix for getting a TV signal when one isn't there - meaning an amplifier doesn't extend the range of the antenna. It merely gives the signal a push along its way from the antenna to the digital tuner (TV, DTV converter, etc). Hopefully, this push is enough to get a good signal to the TV tuner.

Amplified products typically cost more than non-amplified products. So, it's always a good to troubleshoot some typical scenarios that can lead to signal loss before going to the store and spending your money on a product that may or may not fix your reception issue.

Troubleshoot Reception Issues Before Amplifying a Digital TV Signal

Do you use a splitter, RF modulator, or A/B switch? These are common components and a lot of people use them, especially if you are trying to watch and record two channels with a DTV converter box.

The problem with them is that they reduce the strength of the digital signal - meaning it isn't as strong leaving the component as it was entering it. Amplification could boost the signal above the minimum level your components need to produce a good picture.

If you use an outdoor antenna then look at the type of coaxial cable connected between the antenna and line going into the house. Your coaxial cable could be the cause of a poor signal coming into the house.

This signal loss is referred to as attenuation, which is a measurement of signal loss over a distance. In the case of coaxial cables, we're referring to RG59 and RG6. Simply put, RG6 is more digital-friendly than RG59.

In other words, RG59 attenuates more or has more signal loss than RG6. RG59 cable could be the cause of your poor signal. Changing your cable to RG6 (preferably quad-shielded RG6 with gold-plated connectors) could fix your reception problem without using an amplifier.

Of course, buying an amplified product is probably easier than changing out the coaxial cable in your house.

Your current antenna could be the number reason for a poor picture. Mountford says that some antennas could operate up to 50% less efficient processing digital TV signals v. analog.

Mountford's advice on researching antenna issues is the same as mine - go to Antenna Web and use their online tool to analyze TV transmission specifics for your location. You might also try realigning the antenna, but not after going to Antenna Web to get your exact coordinates of where to point it.

Buying an Amplifier

Amplifiers or TV signal boosters are most common in antennas, but you can buy them as stand along products too. Product packaging usually advertises amplified or powered antenna. If you see a db rating then you know it's amplified.

As far as buying advice, just as you can over-water plants, you can over-amplify a digital tuner. It's similar to blowing out stereo speakers by turning up the volume too much.

The hard part is that it's difficult to gauge what's too powerful for your tuner. Some experts I've spoken to recommend amplification around 14db. If you can then buy a product that has adjustable db settings.

If you buy an amplified antenna then be sure to go to Antenna Web to make sure you have you antenna properly aligned before connecting the power.

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