Electrical – Mixing power and signal cables

You do not need to know if there is a 'signal' you just need to know if there is a connection.

A basic tool that can tell you evetrything and costs a few bucks/quid at local hardware store. Multimeter

Never in my life did i have to use a tone generator, a oscilloscope to test if my CCTV, Satellite or TV connection is giving me good enough signal.. LOL

You use that type of equipment for digital/analogue testing where you control several if not hundred outcomes, synchronization and high speed data transfer.

You just need to use a few simple free (brainpower) tricks.

Point A being nearest to your TV and Point B being the other end of the cable.

1. Disconnect all TVs
2. Short point B (so connect the signal and shield with a wire)
3. Test point A with a multimeter set at Ohm

Results

• ~0Ohm or very close to - Woohoo you have a nice connection from a to b!

• 0Ohm More than dead short - You have a bad connection somewhere

• No reading - Cable form Point A to Point B has no connection

There is no need to analyse the signal or test for a signal because you know you have a signal in the other TVs (assuming the coax is connected to the same place)

Alternatives

If you know the coax for all the TVs is the same cable you, you can leave Point B terminated - which is most likely closest to the antenna or after the junction. Test Point C,D...Z respectively to make sure there is a good connection.

Take your TV and connect it to a working plug to make sure the TV is not broke - or as pointed out use TV that works and plug it into your outlet - same difference I think? (but does not eliminate double jeopardy - your TV might still be knackered as well as the signal be broke :) )

Alternative 2

Also requires for all plugs to be disconnected from all TVs. Connect a 9 volt battery to one end and test all the ends for a voltage. If you get ~9 volts then the route is good. If you get a <9V then you have an issue on the route (micro short?) if you have 0V then there's no connection

Good Luck

Multimeter F.A.Q

And a photo to make it look pretty.

Yes, its still valid.

Power and data cable coatings are insulation - designed to protect from electric shock and to avoid short circuits. They do not interfere with magnetic fields.

I do not know what kind of shielding you are talking about - I have never seen any modern power or data cables with shielding that blocks magnetic fields. Magnetic fields are quite pervasive.

In response to your follow up question:

The size and strength of a magnetic field is relative to the amount of current flowing through the wire within. For very low voltage wires, like network cables, bundling them together generally doesn't create a strong enough field to disturb the other lines in the bundle.

However, if you loop the cables, you end up running the same current through very nearly the same space - over, and over, and over - and this can amplify the magnetic field that's created, enough that it can interfere with other signals.

With power cables, they run much more current and so create much bigger fields. Big and strong enough to interfere with the tiny currents going thru the other cables. Looping them is even stronger and more problematic.