The following cable specific terms are used frequently throughout our site.  We have provided definitions to help you better understand their meaning and how they relate to configuration issues. 

Amplification (also known as dB boost): Amplification is the process of boosting a signal. Amplification is generally needed for homes with multiple TVs, or where long cable runs are used. Amplification is generally a good thing, except for the fact that cheap TV amplifiers don't do a real good job, and can actually make the TV signal worse. Cheap amplifiers add "noise" to the signal, which can then be seen as ghosts, buzzing, snow, lines through the picture, and other annoying things. Good amplifiers do their job so well that they don't add ANY noticeable noise to the TV signal. Good amplifiers make your picture look BETTER, and don't cause side effects like ghosts, lines, or snow. The boost is measured in dB. 

Bi-Directional: Bi-directional means that signals can pass in both directions. This means that the cable company can send signals to you, but you can also send signals back to the cable company. Bi-directional has nothing to do with Amplification. Cable signals can be amplified in one direction only, by ONE amplifier. If an amplifier is advertised as amplifying in BOTH directions, be aware that these products are extremely uncommon. To amplify in the return direction, you need a Return Path Amplifier. 

Bi-Directional Amplifiers: Bi-directional amplifiers are the kind that you typically do NOT find on the store shelves, even at your favorite video/electronics store. These amplifiers are different from the cheapie amplifiers for a number of reasons. First, they are generally made of higher quality components. Electroline amplifiers are NOT made in China, although many other brands are. Bi-directional amplifiers use expensive, high tech components which allow them to amplify the TV signal, and at the same time allow your cable box to send signals back to the Cable Company. Bi-directional amplifiers operate in the 50-1000 MHz range,  making them PERFECT for Standard Cable, Digital Cable, interactive services and Cable Modems. Bi-directional amplifiers only amplify the signal going TOWARD your TV or Cable box. They DO NOT amplify signals going back to the cable company, and for that reason they may not always work well with cable modems. Only 1-port or 2-port amplifiers should be used with cable modems for the best results.

Cable Modem: A Cable modem is a piece of equipment which receives data  from your cable company (your Internet provider) and also sends data from your home back to the cable company out onto the Internet. It is always used with your home computer. Cable modems allow you to send information to and from the internet just like a regular modem, except you use the cable company's cable lines instead of the phone company's phone lines. Cable modems use the same signals as your regular cable TV converter box. The only difference is that the cable modems use different frequencies which cannot be seen by your television set. Cable modems generally require a pretty strong signal, which also means that they require a fairly unrestricted path back to the cable company. This is why the cable company will put in a totally separate cable connection dedicated to the cable modem. Cable modems will GENERALLY work in conjunction with a Bi-directional amplifier or splitter as long as the path back to the cable company is not blocked. Depending on the specific situation, a bi-directional amplifier may improve or degrade your cable modem performance. The best rule here is " If it ain't broke, don't break it". If your cable modem is fast and generally reliable, you don't need an amplifier for it. However you might still need an amplifier for the rest of your TV equipment in the house.

dB : TV signals are actually measured in dBmVs. A dBmV is a somewhat complicated to understand reference voltage term used in the TV/Cable industry. In a nutshell, TV signals are transmitted using extremely low voltages (around 1/1000 of 1 volt) of electricity on your cable lines, and what the actual voltages are determines a lot about how your TV picture will look. No, you don't need to understand dBmVs, but you might want to understand how splitters and amplifiers affect  your TV signal, and that is where we talk about dBs. dBs are a RELATIVE measure of how strong your signal is, versus how strong/weak it USED to be.  

F Connector: An F Connector is the screw-on connector used on the back of your TV, VCR, or cable box. It is a standard for all TVs, VCRs, and cable boxes. When replacing cable ends or installing new cables, always use high quality crimp cable connectors. There are different sizes for RG59, RG6, and RG6-quad shielded cables, so be sure to obtain the right ones. 

Frequency Range/Bandwidth: The frequency range (bandwidth) determines what range of signals an amplifier can handle. Basic outdoor Antenna TV and Cable TV signals go from 50~800MHz (MegaHertz), Digital Cable services can go as high as 1000MHz (also known as 1 Gigahertz - GHz). Digital Cable and Cable Converter boxes also require what is called a return path. Cable amplifiers do not provide a return path unless they explicitly advertise that they do. If the amplifier does not support a 5-42 MHz return path, it will not work properly with cable boxes or cable modems.

Unity Gain: 4-port and 8-port Electroline amplifiers come in two versions - those WITH forward gain, and those with UNITY gain. The Unity Gain amplifiers generally have the letters "UG" right on the label (EDA-UG2402 or EDA-UG2802). A unity gain amplifier acts just like a big splitter. It breaks up a cable signal, but does not provide a boost to the signal. This means that "signal strength IN = signal strength OUT". Unity Gain amplifiers are generally used for special applications where you specifically do NOT want any amplification of the signal. Standard amplifiers will provide forward gain, which is expressed as a dB number. 4-port amplifiers generally provide 7dB of "forward gain", and 8-port amplifiers generally provide 4dB of "forward gain". 

Forward Path Equalizing (Tilt) Amplifiers: Equalizing Amplifiers come in only 1-port versions. They are specialized equipment designed to overcome some of the problems associated with very long cable runs. When a cable signal travels over a long cable run (>150 feet), the higher channel (high-band) signals tend to lose strength faster than the lower channel (standard-band) signals. If you use standard amplifiers over long cable runs, you end up with very strong standard-band signals (low channels), and very weak high-band signals (high channels). Essentially you will be able to see the lower channels, but the higher channels may be weak. The opposite may also happen: the standard-band signals may be so strong that they OVERDRIVE your TV or cable box, and the high-band channels may be just fine. The solution to this problem is to install an equalizer over long cable runs. The Electroline EDA-EQ3100 boosts the signal more on some channels than others, so that this "long cable run" problem does not occur.

Return Loss (dB): Every time you put a splitter or amplifier into your cable line, it causes the signals going BACK to the cable company to weaken. This is particularly problematic if you are using a cable modem or Digital Cable Services. If the signal that the cable modem or Digital Converter sends back to the cable company is too weak, your services may not work. Each splitter or amplifier is rated for (return) loss, which basically tells you how much signal strength you lose when the signal goes back through the splitter or amplifier. If a splitter is marked with "3.5 dB", that means you lose 3.5dB of signal, or about 56%.

Return Path:  The Return Path is a special frequency range used by the cable company to transmit signals FROM your cable box BACK TO the cable company. Ever wonder how the cable company can allow you to "talk back" using your cable TV box? How about ordering a Pay-Per-View special using your cable box remote control? The cable TV boxes actually transmit signals BACK to the cable company to tell them that you want to watch the "Wrestlemania" pay-per-view event. Then the cable company sends a signal back to your cable box to "turn on" the pay-per-view channel. That's how they do it. Cable companies also require the return band for use with cable modems. If the cable amplifier does not support the return band, the cable modem won't work. The standard return path is in the 5-42 MHz frequency range. A bi-directional amplifier is required to allow these special cable company signals to travel back to the cable company. CHEAPIE amplifiers will not work with Cable TV Digital services, Multimedia (Cable Modems), and Cable TV boxes.

Return Path (Reverse) Amplifiers: Return Path (Reverse) amplifiers are almost the opposite of the description above, as they amplify ONLY the 5-42 MHz (return band) signals going back to the cable company. A Reverse Path amplifier will help in situations where the RETURN traffic going back to the cable company needs to be boosted, or where the digital cable box or cable modem is unable to consistently transmit information back to the cable company. Usually this is because of long cable runs which tend to decrease the signal significantly.  

RG6, RG59: These terms describe the physical cable used to carry cable signals throughout your home. RG59 is thinner and cheaper, and allows more signal loss. RG6 is a heavier cable which comes in 2 flavors - standard and quad-shield. If you are installing new cables in your house, use quad-shield cable. It costs about 20-30% more than regular RG6, but keeps SIGNAL LOSS at a bare minimum. You should not use RG59 cable unless RG6 is unavailable. Home Depot carries both RG6 and RG6 quad-shield cabling in 100 and 500 foot spools.

Splitter: Splitters are used to break your incoming cable or antenna signal up so that it can go to more than one TV or cable box. Everyone has at least one splitter somewhere. The problem with splitters is that every time you use one, you cut your signal strength down. It's like putting one of those Y-splitter things on your garden hose. You never seem to get enough water pressure (signal strength) after you do that. These drops in strength are also measured in dBs. A high quality two way splitter will generally make you lose 3.5dB. A 4-way splitter will make you lose at least 7dB of signal strength. What does that mean? Well if your signal drops enough, you will get snow or a fuzzy picture. If you use multiple splitters, you actually degrade your TV signals significantly. Splitters also have a Frequency Range. Always use high quality, 1000 MHz DC PASSING splitters. If you use high quality splitters you will save yourself a lot of headaches. They cost more, but they are worth it. cableTVamps.com only sells these high quality 1000 MHz splitters.