TV Aerial/ Sat Amplifiers - How To Pick The Right One
There are lots of different types of TV aerial and satellite amplifiers. Some do one, some the other and some do both. Picking the right TV/Sat amplifier for your installation can be tricky. Especially if its for a communal TV system. In this blog I discuss all the different types of amplifiers used in TV systems. Lets begin!
TV Aerial Amplifiers
All of the following TV amplifiers are intended for use for TV aerial systems only and are compatible with services like Freeview, FreeviewPlay, Youview and BT Vision and can be used for boosting the signal to help overcome signal losses associated with cable lengths and the splitting to multiple TV positions.
Set Back Amplifier
A set back amplifier is a mains powered amplifier with an aerial input and an aerial output. It comes with an electrical plug on it so it can be connected directly to an electrical socket. This are actually one way mains powered TV amplifiers but they are more commonly referred to as “set back amplifiers” in the aerial/ satellite trade as they were commonly installed directly behind TV sets.
A distribution amplifier is a mains powered amplifier with a aerial input(s) and several aerial outputs that can serve multiple TV points. Distribution amplifiers can commonly be sourced with the following outputs:
2 way, 4 way, 6 way, 8 way, 12 way, 16 way.
This means that a 2 way amplifier can feed 2 separate TV sets, a 4 way – 4 TV’s and so on. You could split out of the outputs to serve a greater number of TV’s if required.
DC/ IR Passing Amplifiers – Sky Remote Eye Compatible
If you have a Sky playback system or want one that allows you to be able to view and control your Sky box on other TV’s in your house. This can be done by first routing the aerial signal to your Sky/ Sky+HD box first and connecting into your aerial input on your Sky box. From here the RF1 output can be used to connect your main TV to an aerial connection and the RF2 can then be used to feed back into your distribution amplifier. Doing this will allow the Sky RF signal to be viewed on your TV system. To be able to control the Sky box in other rooms you will need to first turn on the RF power within the Sky installer menu and install magic eyes at every TV position that you want to control the Sky box. If this is going to run through a distribution amplifier this needs to be ‘DC passing’ so that it will pass the DC voltage from the amplifier input to the outputs to power the remote eyes. If the amplifier is not DC passing you will be able to view the Sky around your TV system but not be able to control it.
Distribution Amplifiers with Line Power
A distribution amplifier with line power is not the same as an amplifier that is DC passing. A amplifier with line power usually has a switch on it that will allow a 12V DC signal up the aerial input cable towards the aerial. This is so that the amplifier can also be used as a power supply unit for a masthead amplifier if there is also one connected. I come onto masthead amplifiers later in the article. You should be aware that this type of set up with both a masthead amplifier and a distribution amplifier should only be necessary on very large systems/ buildings and where the signal from the TV aerial is very weak. One stage of amplification should be all that is necessary. Also you need to be careful that you do not overload the distribution amplifier with too much signal as this could cause poor TV reception.
Distribution Amplifiers With Full Output (x+1)
You may come across amplifiers that have a +1 next to the amount of outputs of that particular distribution amplifier. Common examples of this are the following 6+1 way amplifier and 8+1 way amplifier. What this means that as well as it aerial input and the number of outputs, you also have a “full output” which is what the +1 is. The full output delivers the signal with a far greater gain then the rest of the outputs, usually around double as what the other outputs have. Most distribution amplifiers have around 8dB gain on their outputs. The full output will have around 16 dB gain in this scenario. The intention of the full output is that this can go onto feed extra TV points that are fed via a passive splitter or tap off unit which have signal losses associated with them. The extra signal gain from the full output will help overcome this. The full output can also be used for very long cable runs to help overcome the resistance and signal loss over coaxial cable length.
The full output isn’t always a good thing, as the high signal output could actually overload the amplifier itself or the TV tuner itself which could cause poor TV reception. If you do not intend to use the full output on your amplifier I recommend installing a 75ohm resistor on the output.
UHF/ VHF Two Input Distribution Amplifiers
Many distribution amplifiers on the market have more one input. A common type of these are UHF/VHF or TV/FM-DAB amplifiers which have separate inputs for TV and radio aerials. The amplifier acts as a diplexer which combines both signals together, amplifies them and distributes both aerials to all of the signal outputs meaning that you can connect a TV, radio tuner or both on any of the signal outputs. If you want both a TV and radio tuner connected on one of the outputs with only a single cable you will need to split the signal. This can be done with a passive 2 way splitter but an even better way to do this would be to use a diplexer installed in reverse or a diplxed wall-plate that has separate outputs for TV & radio, by doing it this way you will lose less signal than you would with a conventional 2 way splitter.
Most two input amplifiers will allow you to connect either an FM or a DAB aerial into the amplifier. There are not many amplifiers that have separate inputs for both (short of a Loftbox) so if you wanted to introduce both FM and DAB radio signals into your TV system you will either need to install a FM/ DAB diplexer or TV/FM/DAB Triplexer or a “FAB” aerial which is both FM and DAB dipoles in a single antenna with a single cable output.
A Loftbox is essentially a distribution amplifier but with separate multiple inputs for radio, satellite, TV and a modulated CCTV input. I personally never install these as I prefer to install separate diplexers, triplexers amplifier etc but electricians seem to love them. There are a few different models but most typically combine the TV and satellite onto a single cable for the lounge or main TV connection. This means that you will have to install a Triplexed/ Quadplexed wall-plate. The Loftbox usually has a ‘return’input meaning that to send the signals around to the rest of the TV system you will need to feed the signal back in. This can be done with a RF2 connection on a Sky box or by splitting the signal and feeding back in. Alternatively if you do not wish to use the ‘return’ facility you could install a link lead between an output and an input or some models have a switch that you can flick which would make the Loftbox behave more like a standard distribution amplifier.
Please note that the satellite cable input does not mean that you will be able to connect satellite receivers on all of the outputs. You will be able to do this on the main output. If you an amplifier that allows you to connect sat RX at all outputs you will need to install a multi-switch amplifier. It’s likely that the Loftbox will fall in popularity over time with Sky Q as the standard wideband LNB that is used will not be compatible with the system. If you want to know more about how to add CCTV to your Loftbox I advise reading my blog on how to integrate CCTV into a TV system.
Masthead Amplifiers - Line Powered Amplifiers
The best place to amplify a TV aerial signal is up near the aerial, where the signal is strongest and before any signal cable losses have into effect. The problem is that it’s not always possible to get a safe power supply out to the aerial mast and to be honest or wouldn’t be worth it as the coaxial cable itself can be used to power the amplifier. A masthead amplifier and power supply unit is a two part system where the amplify itself is installed nearer the aerial and the power supply is installed further down the cable, usually behind the TV itself. The power supply sends a DC voltage, usually 5-12V DC up the coax cable which powers the amplifier on the masthead output.
Masthead amplifiers as the name suggests are intended for installation on the aerial mast itself, these can be secured in position with a cable tie but this doesn’t mean that they can’t be installed in places where there otherwise is no mains power. Masthead amplifiers are commonly installed in lofts and exterior walls also. In fact, it may be a better idea to install one of these places as it will be easier to access for maintenance or if anything goes wrong in the future. Much more difficult getting out on your roof.
When Sky removed the RF2 from their Sky boxes and replaced with an i/0 link adapter. These did not provide enough power to power these amps so additional power was required. This easily done with the introduction of a power supply unit. The Remote Link Line Amplifiers are not as popular as they used to be with the introduction of Sky Q that doesn’t use the RF2 or i/0 link connection.
Multi-Output Masthead Amplifier
If you want to run multiple TV points of one aerial you will need some sort of splitting equipment to accompany your masthead amplifier. This can be done with a separate DC passing splitter installed after the masthead amplifier that will allow the voltage from the power unit to reach the masthead. A separate all in one solution would be the install a multi-output masthead amplifier which has multiple outputs for extra TV points. The most common version of these is a 4 way version but they can also be obtained with 2, 3, 5, 6 and 8 outputs. I wouldn’t advise getting a two way one in any case because if your ever decided that you wanted another TV you would have to replace the amplifier again. I advise a 4 way in situations like this to future proof the installation.
Remote Link Line Amplifiers
Remote link line amplifiers were a very useful bit of kit. They typically were installed as part of a Sky playback where the multiple TV’s and remote eyes can be connected. The Remote Link Line Amplifiers were typically available in 2 and 4 way models that are powered via the coaxial cable in the input. This could be done via a power supply unit but the RF2 output on the Sky box was most commonly used. This meant that the amplifier could be installed in places where there was otherwise no mains power which could make installation much easier. Larger models with more outputs do exist but these usually require an additional power source as the RF2 is not capable is providing enough power to power the amplifier and connected eyes.
The following amplifiers can be used with for satellite signals.
A lot of people will wonder why the satellite LNB itself is in this article but the LNB should be considered as the first stage of amplification when it comes to satellite reception. Most LNB’s have around 50dB gain but“high gain” models exist also that are helpful for long cable runs.
Satellite Line amplifier
A satellite line amp is an inline device that is designed to overcome cable losses over very long cable lengths. These usually are around 15dB gain and are also usually ‘sloped’ so that the higher frequencies are amplified at a greater level than the lower ones which will suffer greater signal losses over cable length. The positioning of the satellite line amplifier is very important, it needs to be installed somewhere in the middle of the overall cable length. This is because installing it near the satellite dish could cause the signals to become too strong and installing in near the satellite receiver after signal losses have taken effect could mean that there is no signal left to amplify. The line amplifier itself doesn’t require any additional power as this is supplied by the satellite receiver.
Communal TV System Amplifiers
The following amplifiers are for use on very large TV systems, usually only communal TV systems or commercial properties. Please note that I can’t name every single type of amplifier that is used in communal systems as this blog would go on forever, so I have only listed the main ones. Also, where the amplifiers listed are satellite compatible. For this to work you need a satellite dish installed with a Quattro LNB, this has separate Horizontal/Vertical and high/ low bands for the four satellite inputs on the amplifiers.There are a very small number of multi-switch amplifiers like the Optima ones that are compatible with a Quad LNB, but the vast majority are not.
A launch amplifier is usually the first stage of amplification on a communal TV system (if you’re not counting the LNB itself) the dish/terrestrial signals are connected which are then amplified and outputted at very high levels to help overcome the cable lengths on the system which are usually considerable. Most launch amplifiers are around 20-30dB gain but some are as much as 40dB.
4 Input Launch Amplifier
If you see the term 4 input launch amplifier this indicates that this is a satellite only launch amplifier with separate inputs for the four separate satellite bands.
5 Input Launch Amplifier
A five-input launch amplifier indicates that the amplifier has 4 separate inputs for the satellite bands and a terrestrial input for TV aerial and radio(usually) signals. The TV/FM/DAB signals will need to be combined with a triplexer before entering into the launch amplifier.
Terrestrial Only Launch Amplifiers
If you have a MATV or SMATV system with no satellite signals being distributed you will only need a terrestrial launch amplifier for your system. Most will allow TV and Radio signals to both be amplified and some have separate inputs for both. Some models will have as much as 50dB gain.
A multi-switch amplifier is the part of the IRS system that feeds the individual flats/ dwellings on a communal TV system. These usually have five inputs One terrestrial input for TV and radio and four separate inputs for the four satellite bands. Each of the outputs on a multi-switch amplifier will usually be terminated into a Triplexed/ Quadplexed wall-plate in each of the flats to separate the TV/ Radio and satellite signals.
Multi-switch amplifiers come with a variety of outputs, most common are:
8 way, 12 way, 16 way, 24 way, 32, way. Delta even do a 48 way multi-switch amplifier.
Mains Power Multi-switch Amplifiers
A mains powered multi-switch amplifier comes with a 13 amp plug or adapter for a direct connection into a mains electrical socket.
Line Powered Multi-switch Amplifiers
A line powered multi-switch amplifier can be powered via the communal TV system trunk cabling or via a power unit which can send the power via a coaxial cable. The power units required for communal TV systems are much higher powered than domestic power units and are usually 18-24V DC.
Cascade Multi-switch Amplifiers
A cascade multi-switch amplifier is a multi-switch amplifier that as well as having 4/5 inputs and however many outputs, it also has the same amount of trunk outputs as inputs allowing the system to be into further multi-switch amplifiers without any need for any additional splitting equipment. The cascade multi-switch can be powered via the trunk cables meaning that mains power is not always needed at all locations where amplifiers have been installed.
dSCR Multi-switch Amplifiers (Sky Q Compatible)
If you want to make your communal TV system Sky Q compatible. You will need to install dSCR compatible multi-switch amplifiers.These are considerably more expensive than traditional multi-switch amplifiers but the good thing Sky and dSCR is that only one cable is required to be connected to your Sky Q box for it to work properly, unlike Sky+HD or Freesat+/Freetime which requires separate satellite feeds. This means that for the time being at least its common to install communal systems that are half Sky Q compatible and half normal satellite with one feed at least from each amplifier entering each of the flats and terminating into a Quadplexed wall-plate(s). The latest Triax Quadplexed plates are now marked ‘Sat2/Q’ for the intention of connecting the Q box to this terminal. By doing it this way you keep the hardware cost to a minimum due to the increased cost of the dSCR compatible equipment.
Once connected the Sky Q will need to be installed on ‘SCR’ mode.
9 Wire Multi-switches
A nine wire IRS system is a system that has delivers signals from two different satellites for different countries TV. This done with two separate Quattro LNB’s that are installed, either with separate dishes or with a multi-LNB holder on a single dish and 4 cables connecting from each of these LNB’s. Once you add in the terrestrial signals you have a 9 cable backbone and all multi-switches on the system will need to be 9 wire multi-switches for this to work. You only need to install one or two cables from the multi-switch amplifiers into each flat as where the satellite receivers are installed, selecting between the different satellites is done via DiSEqC commands, not via separate cabling.
13 Wire/ 17 Wire Multi-switches
These work of the same principles as the 9-wire system but the 13 wire system is capable is delivering 3 different satellites and the 17 wire 4 different satellites. Obviously there is a substantial amount of cabling that needs to be installed for this type of system and the equipment required is very expensive
TV/ SAT Amplifier Questions - In The Blog Comment Section Please
If you have any questions or comments that you would like to make I will be delighted to receive them. Please leave your comments in the BLOG COMMENT SECTION below and I will get back to your ASAP. I appreciate you patience when doing so as I may not be able to respond as fast as you may like. Please DO NOT CALL OUR TELEPHONE LINES with your questions, there is no one here who can help you and we do not have the staff for this type of thing. Please also DO NOT E-MAIL OR FILL OUT THE WEBSITE CONTACT FORMS unless you are enquiring about having some work done by us. If you send your questions via e-mail or the website contact forms you are likely to either receive no response or receive one asking you to post your question in the blog comment section of the blog that you have read.
Until next time,
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