Treeline said:
Nope, I was not clear. It's an outside antenna that I cut into thirds.
Think more of a phone line feeding several rooms.
An antenna lead isn't like a phone line. It is a transmission line, and
should be terminated at one end with a resistance equal to its
characteristic impedance to minimise reflections (ghosts) - the antenna
inputs on TV sets always have such a terminating resistor built in.
I wanted to make the unused or last two cut portions useful again
just for closure, as we say.
Probably not a good idea.
I did not quite get this. The twin-lead just needs a balun transformer
to go into the TV. An existing internal loop antenna appears to operate
independently.
The coaxial cable normally used to hook up TVs has a characteristic
impedance of 75R, so the coax socket on the the TV is designed to
present a 75R resistive impedance to terminate such a cable. As you
say, the internal loop antenna operates independently.
CTV monitors, which are often used to display the same picture in
different places, tend not to have a built-in 75R termination, and rely
on the installation technician plugging in a 75R terminating resistor
(mounted in a 75R connector) on the monitor at the end of the cable.
The balun transformer you use to convert from 300R twin cable to 75R
coax is a 2:1 step-down transformer, so that the 75R termination in the
TV set looks like a 300R termination to the 300R twin cable
You or I was not clear that there is a real outside antenna, the twinlead
antenna wire is just that, nothing more, quote the raven.
He was just a fussbudget. Imagine, after inventing calculus, he gets all
bent out of shape because Leibniz invented it too, and a far more useful
version we use d/dx. Poor Leibniz. Newton was NASTY.
Newton invented fluxions - I don't think that his notation was any less
useful than Leibniz's, but because he didn't publish it, it was never
widely adopted. Newton wasn't just nasty to Leibniz - his treatment of
Hooke adn Wren was pretty shabby too.
If I could ask questions in a way that suggests I might understand the
answer, I probably would not need to ask at all but could simply
find the canned answers on the internet.
I see your point. This was probably too advanced a newsgroup to ask
questions in or the people in this newsgroup are tired of questions
they consider ambiguous.
I wonder if I could suggest that you need to answer questions so I
could understand my own question.
You know the routine if you ever taught college:
I gather what you meant to ask me was......
We do a lot of that here. The trick to getting a good answer here (as
in most forums) is to pose concrete questions based on what you want to
achieve, expressed in terms you do understand, rather than waffling on
about stuff you don't understand.
I've spent about thirty years solving people's electronic problems, and
it always takes a while for me to drill down to the level where I
understand the client's problem in a way that admits of an electronic
answer - and I'm better at it than most.
