TV aerial amplifiers

About a three years ago there was a lot of pixelation on our TV. The local aerial installer said everyone in the area need an amplifier and fitted a masthead Antiference which solved the problem.
Over Christmas we started to get pixelation again, which at first I thought was due to strong winds, but it has continued into the current cold but calm weather.
I had a look today (being naive I thought there might be a battery) but all seems ok, connections OK and no obvious signs of weather damage. However, after a Quick Look on the internet I realised it is usually supplied with a power supply module which I don’t seem to have…and yet it used to work perfectly.
I’m not aware of any new installations around here that might be adding interference to the signal, and I don’t think it is linked to aircraft - in fact we get quite a bit of military helicopter flights but they haven’t caused a problem before.
Could the current weather conditions be the problem? Or should I try to get a power supply?
NB the signal goes via a BT box pro, streaming is fine, but the pixelation occurs on the Freeview box in the TV as well so I doubt it is the BT box at fault.

People get pixelation using a booster from a weak signal but if you installed a proper high gain Digital Aerial and point to your main transmitter then you shouldn’t have to use boosters.
Single line twig to telly is best anything shared adds it’s issues.
Usually regular retuning of the telly helps as transmitters use Multiplex and they swap frequencies round sometime.
Trade nickname is Musical Muxes.
Oh and dodgy old coax cable can cause pixelation too.
I use.
WF100 / CT100 cable “Double Screened” (copper/copper) & CAI approved.
It is suitable for FM, DAB, TV and Satellite (6.6mm thick and 75 Ohm impedance).


Possibly worth checking the cable for damage, especially at outdoor terminations.
Mobile phone signals can interfere with TV signals. If a new antenna has been erected nearby, or an old one replaced, that’s a possible culprit.

There’s an excellent knowledge database on an aerials and tv website. I’ll leave you to google that - but the crucial thing is this:
“if the signal is of poor quality and one adds an amplifier it will give no improvement.”


We have an aerial shared with a neighbour (developers!!!).

It has a box on the aerial and each house has a distributer block in a store room on the top floor (town house), that supplies the power to the aerial box. It distributes the signal to other aerial outlets as well.

Maybe you have something similar tucked away somewhere and someone has turned the socket off.

This is it

Right - plenty to check out there…especially the co-ax as yes, it is a bit old and wasn’t replaced when the amplifier was installed, and I’ll do a retune as well.
As for the mobile signals - interesting. We’ve just had a smart meter installed (long story, but it doesn’t work as it can’t pick up the O2/DCC signal) - maybe that’s interfering as it tries to get a signal?

Good luck
A retune can help but good cable and strong signal not a boosted poor one is better. :+1:t2:

Some tvs can act as power supply. Mine (Loewe) only started to work when I enabled that. Maybe you have had a firmware update and the power supply is now off?

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with regards powering the masthead amp, note that some TV boxes have the ability to do that, often as an optional configuration in the setup, so you might want to check in the settings of the BT box to see if there is such an option and that it is enabled.

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Have you added/replaced any LED lights or their drivers? I find these can interfere with the TV and especially with the radio.

The suggestions about the TV box providing phantom power for the masthead amp makes a lot of sense if you have no other power supply - worth checking nothing has changed there. If the problems occurred after high winds and if the aerial looks ok physically (no missing front elements or reflector and no damage to the dipole assembly and junction box) then is the alignment to the transmitter still ok ?

I’d suggest if nothing obvious is amiss then it’s worth getting a decent aerial installer in to check things out properly, to make sure all is well with the aerial, amp and cabling. They can check aerial alignment and signal levels are good from your local transmitter.

I’m assuming there is no maintenance going on on your local transmitter. Any neighbours having similar issues ?

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Not all mast head boosters use power.
I’ve fitted a few.
They work on a similar principle as an SUT

Passive Amplification

Passive amplification, on the other hand, relies on passive components like resistors, capacitors, and transformers to transfer energy from one part of a circuit to another. Passive amplifiers do not require an external power source and typically provide less gain than their active counterparts.

Resistor-Capacitor (RC) Coupling: RC coupling uses a combination of resistors and capacitors to transfer AC signals from one stage to another while blocking DC components. This method is often employed in audio frequency and low-frequency applications due to its low cost, simplicity, and effective filtering capabilities.

I would recommend a TV Antenna Tech to have a look.

Does it happen all the time or only at specific times of day, and is the pixelation available on all channels?

Mitch in Oz.

Why wouldn’t you just stream your TV?

I would suggest from a technical perspective a ‘passive amplifier’ is a contradiction in terms… if you have solved that you have solved the world’s energy problems for ever. Anything that is passive is a filter/transformer, things that are active can amplify.

Many mast head amplifiers including Satellite LNBs use power provided over coax from the tuner/TV/STB… so as suggested worth checking that has not been disabled if used. They are called Bias Tees… ie they bias DC into the coax.
Assuming ok, as suggested elsewhere I would check coax.
Other than that get a proper rigger who will have their test equipment and can track the signal through… as otherwise could be like looking for a needle in a hay stack.
Issues can sometimes to do with signal quality, ie distortion, and not signal level. Of course with digital you can’t ‘hear’ this so without test equipment hard to determine.

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Fortunately it seems to be the cable - after changing it the picture has been fine for a few days, so fingers crossed.


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