How to test a TV aerial wall socket?

[Bert Coules]

I suspect that this is a very daft question, but here goes anyway...

The unfurnished bungalow I'm renovating for sale has two separate TV aerial socket boxes. One is on an outside wall and it's easy to trace the cabling up to a fairly new chimney-mounted aerial. The other is on an inside wall and the cabling is completely buried: I suspect that it goes to a loft aerial, but the loft is not easily accessible for a look, and of course after the digital switchover a loft aerial might well be useless anyway.

Is there any convenient way to check if the second socket is relaying a signal, other than bringing a modern TV (or an older set plus a digibox or similar) into the house? If the socket is useless I'd rather remove it than leave it for a new purchaser to be disappointed and annoyed by.

Many thanks.

[John Rumm]

I think you may be over thinking this ;-)

However, the viable tests are plug in a TV and try, or plug in a test meter and measure. Whereabouts in the country is the aforementioned property?

[Bill Wright]

Most likely the second one was the original from wayback. The cable will very likely go to the loft. Have a look behind the socket, see whether the cable goes up down or sideways. Irrespective of whether there's an aerial at the end of it, it could be useful if the resident wants to put a TV set or FM/DAB radio there. A cable to the loft is very helpful for connecting an outdoor aerial, especially if the socket isn't on an outside wall.

After switchover loft aerials are more likely to work, not less likely.

If the cable is pre-1970 it could be the very old type of co-ax which isn't really any good for modern use. Even if the cable is newer it might be affected by damp, or it might be damaged in the wall.

If it appears to be very old thin cable, but there is an actual duct (pipe) from the backbox going upwards (typical of 1950/60s upmarket houses), remove the socket and replace with a blank wallplate. Possibly label this 'duct to loft'. Leave the old cable in as a draw wire.

Bill

Bill

[Bert Coules]

Well, maybe...

Ah, I didn't know that.

FM reception in the area is worse than useless, but a vertical(ish) cable run, even if there's not an aerial at the end of it, could well be useful for a DAB radio I suppose. Nice point.

Thanks to you both.

[Bill Wright]

I know the area and the FM isn't all that bad. A loft aerial should work fine.

Only if you use the screen of the cable as the sole conductor. And not if it's in steel conduit.

Bill

[Bill Wright]

Likely to be outdated cable then.

No it ain't. Do as I said. Leave it as a draw wire. You're over complicating things.

Bill

[Frank Erskine]

Not really. You can buy a basic digital telly from Asda for some 70 quid (or so I'm told). Plug it in and see what useable reception you get :-)

Unless you have a spectrum analyser...

[chrisj.doran%proemail.co.uk]

USB TV dongles are only a few quid on eBay.

Chris

[Andy Burns]

After DSO a loft aerial is likely to perform as well for digital telly as it currently does for analogue telly ...

[The Natural Philosopher]

if you have a laptop PC get a basic telly dongle from Hauppage etc. Should be about £30.

[The Natural Philosopher]

Depends on how far they moved teh TX frequencies.

For sure mine are all over the place now - narrow band doesn't cut it anymore

[Martin Brown]

Digibox and an LCD monitor? But why not leave it for the new owner to sort out?

Getting the *cosmetic* appearance right is by far the most important.

But why are you doing this?

AFAICT from the houses I have bought it is traditional for electricians and DIYers to rig the place up with as many dangerous booby traps as they can think of to catch out the new occupant.

Over past moves I have found:

Wall lamps spurred off the ring main.

13A sockets off the immersion heater supply. Multiple light switches with one ring main switched load on it. Ring main cross linked to boiler circuit in the main box. Switches between two different isolator outputs and a load. Loose floorboards held in place only by carpet.

The list of traps that old houses contain is endless.

[Bert Coules]

Chris,

That's an idea. I could take in a laptop very easily. Thanks.

[Bert Coules]

Because it seems to me to be both polite and considerate to do so.

[John Rumm]

You probably need a group E now (assuming you are using the main Sudbury Tx)

[The Natural Philosopher]

I went that way some time ago.

Now the power levels are well up its pretty much faultless. Haven't had a sporadic E or whatever it is screwing up a MUX for over a year.

[Graham.]

There was a lift on this morning, I could hear several European FM stations on 87.6 MHz

[Bert Coules]

Just to draw a line under this, I had the chance today to test both aerials, the roof and the loft. Both gave fine results for Freeview.