Terrestrial interference query.

cornholiooo

The setup is as follows....

Wide-band UHF (contract) aerial installed in attic, (in an area of strong signal) tested with horizon terrestrial meter and its perfect.

There's about 4 ft of new RG6 leaving the aerial, straight into a (also new) Wolsey 4 Way IR Pass Amplifier with LTE Protection from 4G interference

There are two of the (out) ports being used. One cable is running to a Samsung TV (Saorview compatible) and the other to a Triax HDS 537 combi receiver.

From the aforementioned dist. amp to both tv points is all old coax, of questionable quality.

Under normal use the Saorview channels are perfect. As soon as the electric shower is switched on (its approx. 4m from one tv and 8m from the other, in a bungalow) the pictures start to deteriorate.

On the Saorview TV the picture starts to patch badly and the audio stops intermittently.

On the TV connected to the STB the picture goes black and then reappears roughly every second. I have seen an incident before where an electric fence around three sides of a house produced a similar affect on an identical box.

The satellite channels in both locations remain unaffected. (RG6 I might add.

When I test both points with my meter while the shower is running there is a significant drop at both.

On the coax going to the Saorview TV there is a diplexer being used to combine the satellite and rtes.

I cant think of anything else... as in system details...

Solution anyone?

Thanks in advance for any help.

Peter Rhea

I'd look for a loose connection in the shower circuit before anything else. Arcing could be causing interference. Get an electrician if you have to.

Souriau

What strength is the signal from the aerial, reading on your Horizon meter?
I have found from past that when is too high, at the high end, it also picked up interference as well
e.g I had 80 dBµv, everything is working well no break up until the neighbour start using his lawnmower or the farmer going pass in his tractor with Beacon light flashing.
I reduced the signal strength down to 60dBµv and that had sorted all interference problems out.

Peter Rhea

If it isn't an issue with the shower circuit, I would be surprised. Specially with the aerial being in the attic & all.

cornholiooo

Peter Rhea wrote: »

I'd look for a loose connection in the shower circuit before anything else. Arcing could be causing interference. Get an electrician if you have to.

Souriau wrote: »

What strength is the signal from the aerial

The homeowner did inform me that he had at some stage dismantled the shower unit and as he said himself 'replaced the brushes'????? Personally, I will wire a plug but that's about it as far as working with electricity goes. I'll tell him that he should get a proper sparks to check it out so.

Testing the aerial on its own before the dist. amp..... my meter displays a rating out of 5 (*) and a pass/fail indicator. It gives me a reading of 5*'s, the reading in dBµv shoots up to <40, also the spectrum display is healthy looking. I am not as educated or qualified as some of you guys on here, but in saying that these readings are conducive in my experience with trouble-free Saorview.

Thanks guys, any other input greatly appreciated, ill post the solution if the problem is resolved.

deadduck

i'd be interested in hearing the solution to this too, as I am having (what I think is) a similar problem.

our saorview aerial is in the attic, but whenever the living room or bedroom thermostats click on or off, the picture breaks up for 1 - 2 seconds. and like your issue, the sattelite pic remains unaffected?

zg3409

Showers pump use brushes, which naturally spark as the pump runs. This could cause interference, however if the signal to the TV is improved the problem may go away.

I would attempt to remove the distribution amp, and just feed a single TV as see if the problem is gone.

Naturally moving the aerial outside might give a stronger signal and remove the need for the amp too.

In theory you can reduce the interference by putting filters on the shower, but if you want to avoid messing with mains electricity, it's best to try remove the amp, and improve the wanted signal. No amp and an attenautor before the receiver might help too.

Peter Rhea

deadduck wrote: »

. . . our saorview aerial is in the attic, but whenever the living room or bedroom thermostats click on or off, the picture breaks up for 1 - 2 seconds.

Moving the aerial outside will lower the effects of interference from within the house & will give you a stronger wanted signal than you get in the attic, provided you site the aerial correctly.

Also, some aerials are more prone to picking up interference from below, due to their not being properly specced for direct connection to coaxial cable.

winston_1

But if the shower is causing interference it needs fixing. Neighbours could be affected.

zg3409

Any sort of motor, such as lawnmower, electric kitchen knife, food mixer etc. will create a certain amount of radio noise. Even turning on or off a light switch can also create a spark which can cause a glitch on the TV or more constant trouble.

In most cases the best fix is to improve reception, rather than trying to stop all noise sources. There are supressors you can buy and are often already fitted to such items, but if your TV signal is right on the weak level, it may still cause problems with the supressors fitted. Anything that moves and creates sparks, will cause interference.