TV Aerial Socket

[rozza]

Hi All,

I have a couple of questions that I need cleared up. I moved into a flat 18 months ago and have noticed that in high winds or heavy rain the signal goes from the TV. I assume this is most likely from the aerial moving/ bad connection somewhere?

I have spoken with the management company and they have said they have received no other complaints and that it must be my own connection. Short of getting someone out to look at it what can I do? What can I look for?

I have removed the wall plate and noticed there are 2 cables attached (I only have one socket). The wall plate appears to be un-shielded. I have thought about replacing this but not sure what socket i can use as all the other appear to be for only 1 cable. What do you recommend?

Thank you in advance
R

 

[ericmark]

I would try easy first try using a signal booster
Some TV's are better than others receiving.
When I tried using a freeview box on my old aerial it was useless but when I got new TV with freeview built in most channels work.
Unlikely a new wall plate will help.

 

[rozza]

I had the same problems with my old TV and have just bought a new LCD TV with freeview which has helped until the last few weeks of bad weather. I also use a signal booster which helps marginally when the signal deteriorates.

I am currently using an internal aerial and booster which isn't too bad - just wish I could plug it into the wall so it would work.

Does anyone have any ideas as to why there would be two wires for the wall plate?

 

[radioredcat]

The first thing you should do is ask your neighbours if they have any problems with reception.
As to the two cables are they the same size? how are they connected to the plate? a picture would help.

In some cases depening how old the property is it is the norm to have two cables on for TV and FM radio if it dates back to 60's-70's there's usually tv coax 6mm and a thinner coax for FM.

From the 80's onwards they should have used the same coax for both,It has been known for tv communal systems to be daisy from one flat to another that is completely wrong but it does happen.
Today they put extra coaxes in for sky but until i know how it's connected i can only guess.

Bad reception when it rains is indicative of water getting in the coax usually from the aerial the tell tale signs are analogue pictures going grainy,ghosting may affect just some channels,With digital could loose several channels.
If it is water getting in the coax then it would affect everyones reception on a communal system that is assuming that you have a communal system.


andy

 

[ericmark]

Have you upset anyone? I know of people who thought it was funny sticking a pin through the cable.

 

[rozza]

I probably have upset someone but don't think he is likely to have stuck a pin through the cable, but I guess you never know!

The two cables apepar to be the same size (black sheathed coax cables) probably around the 6mm size. One appears to be coming into the box from the ceiling direction and the other from below. The back of the plate is a square plate (approx 3cm x 3cm) the first cable (from above) is attached top the middle of the plat. The second cable (from below) is attached to the corner of the plate. I'll double check tonight and post a picture. I don't trust anything in the block as they have done some things really badly and completely cut corners in other areas.

The property is 60s so could be for TV and FM but I'll double check the cables. There is a box oin the communal stairwell that I assumed was a booster box for the tv but haven't looked at this for a while, again I'll check tonight.

I thought about removing the second cable and seeing if there were any complaints! Having spoken with the management company nobody else appears to have complained though I'll knock on a couple of doors tonight. We're not allowed sky dishes on our block so there shouldn't by sky at all.

The analogue pictures do go grainy and we definately loose some if not all of the digital channels, especially when it rains. I guess I'll have to get up onto the roof and check. This may be an obvious answer but how do I check if waters getting into the coax cable? If that is the problem what can I do about it?

Thanks so much for your help.

R

 

[radioredcat]

If water gets in air spaced coax that means there are holes running through inner insulation (technical term dielectric).

Can you imagine my supprise when i walked into my mothers house and saw water runing down the screen as the setop box was on top of the tv.
She said the reception was bad.

Some years ago i was asked to look at a tv that would not come out standby so when went to look at it sure enough it would not come on.
So i went to take the back off and when i pulled the aerial plug out it was wet,so when i took the back off the circuit board was wet through so i dried it off with a hairdrier and when i switched it on it worked perfectly they were very lucky.
He did comment that the reception had gone bad.
Some coax have a solid dielectric so water won't come down the cable but will corrode the copper.

If water gets in the coax from the aerial on a communal system the water will only get to the distribution equipment but it would affect all the signals in the flats.
I know plenty flats that have thier own aerials so is it a possibility that you have your own aerial?.

I would check with your neighbours first,That outlet plate sounds odd unless it is a plate that incorporates a splitter so one connection might go to another flat.

andy

 

[securespark]

PICTURES!!

 

[rozza]

Photos as requested.

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• rozza
• 10 Feb 2009
• 1

Box in the communal stairwell

Untitled

• rozza
• 10 Feb 2009
• 1

Set-up in communal stairwell. There appears to be one cable coming fromt he roof and three other cables heading towards the three flats on our floor.

Untitled

• rozza
• 10 Feb 2009
• 2

The socket in my flat. Note the two cables.

Untitled

• rozza
• 10 Feb 2009
• 1

Thanks for the help so far.

R

 

[ericmark]

I would like to see what radioredcap thinks but I think that amp is only amplifying the supply to one flat.
Seems there is three inlets and one outlet these are normally used to combine sky, TV and Radio into one coax and then there is a special wall plate which splits them again.

 

[radioredcat]

Iv'e had a look at the pics and the socket in your flat looks like a splitter plate so somebody else must be connected to it.
From the pics the cable at the top of the plate looks a bit dodgy so check the the outer braid is not touching the inner.
Wall plates are notorious for being faulty they tend to get knocked the cable should be curled neatly so it doesn't kink when you put it back.

The aerial cable from the roof has a 10db attenuator into a 0-20db vaiable attenuator into the distribuion amplifier and then the output is split for the flats.
The job of the attenuator is to reduce the incoming signal level to prevent the amplifier overloading.
But as your reception is varying when it rains it's got to be water getting in the aerial connector box or the coax,What usually hapens with coax lying on the roof it gets blown about with the wind and wears the outer sheathing and then water gets in.
The coax shown doesn't look like air spaced coax so you need to find why the reception is varying.

You could try adjusting the varible attenuator (the square box with the red knob) making a note of it's position so you can put it back.
The only problem with doing that is there's a fault and will probibly get worse so adjusting the attenuator is masking the fault.

When the system was installed over the years things change trees grow in the signal path and they can cause reception variations when it rains gets worse in summer and something gets built but i don't think this is your problem.

I have a look at the aerial and coax on the roof covers do go missing on the connector box.

If your neighbours are getting good reception then it will probibly be the socket which you can buy from a repituble aerial dealer and you need to get like for like.

Check with your neighbours first.

andy

 

[radioredcat]

I would like to see what radioredcap thinks but I think that amp is only amplifying the supply to one flat.
Seems there is three inlets and one outlet these are normally used to combine sky, TV and Radio into one coax and then there is a special wall plate which splits them again.

The output from the amp goes into passive splitters (the 2 grey boxes under the amp) the signal output from the amp is set by adjuster on the amp itself and the signal input is set by the variable attenuator.

Maybe all his neighbours might have cable tv.

andy

 

[ericmark]

A thought Andy could the box be there to supply a mast mounted amp with DC? If so water could still be problem and power may be failing when it rains.
But can't really see how the flat owner can get around these problems.
I would have thought this is all down to the land lord?

 

[ericmark]

Good point Andy my Freeview is useless but I use sky so have no reason to complain and with not having cable hear I had not thought of that.
Maybe better to use www.tvcatchup.com which is poor man's cable?

 

[radioredcat]

I don't think there will be a masthead amp but we won't know till he gets up there and has a look and i don't think that amp supplies power via the aerial connectors they it usually says on the box.
It's a good point though if there is an masthead amp it would have to be supplied up there as well.
Your right about the landlord it is there responsibility and they are not using their loaf because if he disconnects the cables another flat looses their tv.
The other thing is if they get someone out they will end up putting the rent up so if it's only going to cost a few quid then it might be worth him doing it.
But he has bad reception then the others must also.

whats the problem with your freeview if you can receive channel five then freeview should be ok from winter hill.
Alternatively there's storeton on the wirral.

http://www.ukfree.tv/txdetail.php?a=SD660144
http://www.ukfree.tv/txdetail.php?a=SJ314841

I have done some tests on two transmitters by reducing the signal so digital works ok but analogue pics are very grainy.
By the way iv'e used tvcatchup and it seems ok.
andy