How can it happen with Coaxial cable?

Years before- when i was a young'un, a TV cable wire had a break in between.
I stripped off the plastic insulation, and connected the central core(wire) of each other making wires like a hook, so that it would be in place and hang. I did not connect the outer metal shield though. I received a good reception in my television, though i had not connected the outer metal shield with each other.

I suppose the metal wire acts like 'Supply' and shield acts like a ground...How can current flow without a ground? How can i get a good reception?

**broken link removed**

Current doesn't flow, it worked (only badly) because the capacitance between the two screens enabled it to 'jump across' the gap.

However, this would only happen with VERY strong signals, overwise signal loss would be noticed, and may not work at all..

r.vittalkiran said:

Years before- when i was a young'un, [/I][/B]

**broken link removed**

Click to expand...

Hey I thought you were a kid. Summed you up incorrectly.

My bad

Cheers

lol... i could'nt have used ETO if i was so young. Like i was 10 at that time.

im not exactly sure why that would happen. but i geuss its like an AC signal, i noticed my AC circuit analysis class that only one lead from the function generator (AC generator) could be connected to the circuit and i would see the wave on the scope (instrument that measures AC current), anyway i know that the tv is grounded so maybe the current flowed that way? also i know that with AC you have a HOT line and a neutral line. where the neutral line carries no current and the HOT line has voltage on it so if you were to touch just the neutral you wouldnt get shocked, but if you touch just the HOT then you will...

Tv antenna's such as a beam antenna have basically a dipole for feed .
The center conductor goes to one side and the shield to the other side.
Using just the center conductor is like having a very short "Long wire" antenna.
Minimal signal, but there is something there.
You must have been in a very strong signal area.

unix60959 said:

im not exactly sure why that would happen. ...

Click to expand...

That was another case, it even happened to me.
But still not sure 'why?'

As 'Nigel Goodwin' said: Current doesn't flow, it worked (only badly) because the capacitance between the two screens enabled it to 'jump across' the gap.
It would be the reason, but i still need explanation to it.

r.vittalkiran said:

That was another case, it even happened to me.
But still not sure 'why?'

As 'Nigel Goodwin' said: Current doesn't flow, it worked (only badly) because the capacitance between the two screens enabled it to 'jump across' the gap.
It would be the reason, but i still need explanation to it.

Click to expand...

Why would you need further explaination? - AC travels through capacitors, you effectively have a capacitor, so the AC travels through it - it's not rocket science.

TV uses VHF and UHF frequencies. The capacitance between the two cable shields is very low but is enough to couple the very high frequencies.

Another way to look at this situation is that the real antenna and the top section of coax are creating a "long wire" antenna which is connected to the centre of the lower section of the coax.

Whichever way you like to think of it, it is a poor antenna which may work sufficiently well in some circumstances, but dont expect it to be reliable.

JimB