There are high chances that this is the first time you hear about a TV/SAT attenuator. However, as an Aerial Fitter in Preston we do use these from time to time.

Before diving into this subject, I am aware that for most people, a lot of what is discussed in this blog are terms and subjects that are only of interest to other aerial & satellite engineers. The general public don’t really care how their TV works, so long as it does! It is only when they experience a problem, that some begin to take an interest. With that in mind, I will be discussing about a small often overlooked piece of equipment that does on occasion come in very handy. This is the Attenuator.

So, what is an attenuator & what is it used for? Well in simple terms an attenuator is the reverse of an amplifier. Whereas an amplifier amplifies or increases a signal or sound, the attenuator reduces the signal or sound. In our case we look to it in order to reduce a satellite or digital signal from an aerial.
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They are only small pieces of equipment and come with differing rates of signal reduction. It acts like a resistor and depending on the strength it is set to. There are attenuators that have a fixed amount set, such as a -10db reduction or there is the variable type that allows the amount to be set manually. They are designed in a way to provide a reduction or resistance in the signal without distorting it.

The reasons they are used is to reduce the strength of a signal going to the television if the signal is too strong. The reason a strong digital signal can be a problem, is that if the signal going to the TV is over 90db then most TV’s will struggle to deal with that signal. This is known as over signalling.

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When this happens, the result is almost identical to having a very poor signal. Picture break up, freezing, sharp loud noises. On the odd occasion I come across this, I am called out because the customer thinks their aerial is failing and the signal is too weak. The ability of an attenuator to reduce the signal is a very simple solution and cost effective.

Why can a signal be too strong. Well, in my experience, one of the most common reasons, and in reality, it isn’t that common, is due to the set up of either 1 or more amplifiers. Not all homes are set up have a nice neat and orderly set up of its aerial system. Larger homes and businesses such as rest homes and hotels will quite often have one system on top of another.

Due to this I will often come across a set up where a set back amplifier is feeding into another amplifier and then into another. All of this is a complete no no when it comes to providing a trouble-free distribution system, but it happens never the less. In most cases a complete redesign and installation is not affordable, and a quicker and cheaper solution is required for the TV’s suffering from over signalling.
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This is where I will employ the use of an attenuator for each of the TV’s suffering with over signalling. It would be better to remove the amplifier distributing to the TV’s but sometimes this isn’t always the cheaper solution for the customer.

​Why?

1. Firstly, it can be very difficult to track the cable back to the amplifier (particularly within hotels that have dozens of rooms with TV’s in them)
2. It maybe the case that only a few of the outputs from the amp result in over signalling due to the run of the cables coming from and going to the television. (A shorter run of cable loses less db than a longer run).

So, for these reasons, using an attenuator each of the TV’s can sometimes be the best solution.

Digitec Aerials Preston
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The Watermark,9 – 15 Ribbleton Lane,Preston,PR1 5EZ

Telephone:  01772 369629 ​

I recently received a question from someone that had just moved into a new build property. They asked whether it would be possible to install a satellite dish for Freesat in the loft space. After quizzing the homeowner as to why they would want it in the loft, they said that the builders had run the twin satellite cable from the downstairs living room in to the loft along with the aerial cables.
So, giving that the cables were already there, they’d assumed that it was possible to successfully install a satellite dish within the loft, more information here. 

In order for a satellite dish to receive a good enough signal to use, it must have an unobscured line of sight. That means it cannot have anything in the way of the signal, such as buildings, trees and even branches with block a signal. Therefore, installing it within a loft would prohibit the dish from receiving any signal whatsoever. Unlike the signal for a TV aerial, the signal from the satellites that are in geostationary orbit is weaker and simply will not penetrate through the roof of a house.
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So, if the satellite dish can’t be fitted in a loft, why are there satellite cables there? Well, in the process of installing the cable for the house, the fitter, usually an electrician runs the coax cable for the aerial points to one place in the loft, in order for an aerial installer to join to when fitting an aerial in the loft. It makes sense then to run the satellite cables there too, since all of the cables for the TV points can then be found in one place.
The electrician won’t know when installing the satellite cables, where exactly on the property the freesat or sky dish will be fitted. Due to this a central location that is easy to find is the best place for them to be run. The loft is the logical place for this. All the satellite engineer needs to do is to route the cables from the newly installed dish into the loft and connect up to the pre-installed cables.

One of the reasons why we sometimes get asked if it is possible to fit a satellite dish in a loft is for the aesthetics of it. Some people really don’t like the look of either an aerial or a satellite dish on their property. They would prefer it was completely out of sight, including the cables. One of the services we provide is this kind of installation, but in all honesty there is only so much we can do. As mentioned before, the satellite dish must have a completely clear line of sight and this can restrict where on a property it can go. Then there is the run of cables and depending how many cables need running to which rooms in the house.

All of this can kind of hinder the attempt to reduce the visibility of unsightly cables and a satellite dish. However, if it can be done we can do it. We find that mounting a dish in a discreet location such as on a chimney stack for instance immediately reduces its visibility. Second, by running cable behind drain pipes and under the eaves can also make the wiring less visible. We have on a number of occasions fitted a sky dish to a pole at the bottom of a garden.
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Each property is different but in most cases a discreet satellite installation can be possible to do.

Digitec Aerials Preston
Address: The Watermark,9 – 15 Ribbleton Lane,Preston,PR1 5EZ

Telephone:  01772 369629