TV aerial problem - co-axial plug

travel_freak

Hi, I hope someone can throw some light on this strange happening...

I have an external TV aerial. It previously did not have any co-axial plug on it - this is the little metal bit which enables you to plug it into the back of the TV. It just had the bare bit of copper wire.

I bought new co-axial plugs and wired it up but something very strange is happening.

As soon as I put the metal bit on and plug it in to the TV the reception is really lousy. But if I take off the metal casing, so just leaving the plastic inner part (with the copper bit screwed inside it) that plugs in fine and the reception is perfect.

I don't understand why putting the whole thing together - as it should be - makes the reception worse.

I could just leave the metal casing off but feel a bit frustrated by this and would really like to know why it won't work!! If anyone has any ideas I'd be really grateful.

Regards,

Lorian

There is a short between the inner and outer cable braid. This is most likely to have happened at the end you have put on, but it could be a the aerial end, or somewhere else if the coax has been pinched badly.

Just one little copper strand in the wrong place will do this.

L.

travel_freak

Thanks Lorian,

There are some stray sort of lining bits of thin copper and I thought the instructions said to wrap this around the plastic insulating core of the wire which is what I did. Then there is a bit of metal that you sort of pinch over this and then the metal casing which screws into the bottom bit to secure (hope I haven't lost you yet!).

Should i just cut off all these stray bits of thin copper rather than wrapping them around the plastic insulating core?

The only bit of the assembly that has been pinched is the bit that sort of has flaps that I think you need to pinch to close over the wire?

Many thanks.

albertross_2

The pinching bit of metal is the thing that should hold them back, when you tighten the screw thread.

mcfisco

Have a look here
http://www.sat*cure.co.uk/tech/plugs.htm

Scoll down to 'Fitting A TV Plug'

You'll need to remove the * from the middle of the web address as for some reason the name that it should be gets filtered out.