How far have radio signals traveled?

How long would it take to send a signal to somewhere like Alpha Centauri, and have we attempted to send signals to neighboring solar systems?

"How long would it take to send a signal to somewhere like Alpha Centauri?"
A radio signal to Alpha Centauri would take about 4.5 years to get there from Earth. You can determine the time for a radio signal to get from Earth to some distant point simply by finding out how many light years that point is from us. A light year is the distance light travels in one year, and radio signals are nothing more than a form of light. So if a star is 100 light years away it would take a radio signal 100 years to get there.

"have we attempted to send signals to neighboring solar systems?"
We haven't beamed any signal directly at any specific solar system, but about 25 years ago we beamed one towards the
Great Cluster in Hercules, Messier 13. The globular cluster is 25,000 light-years away in our galaxy, the Milky Way. So far, moving at the speed of light, the message has traveled only one thousandth of the distance, or about 147 trillion miles.

if a star is 4 light years away, it takes radio signals 4 years to reach there...
so since radio was invented on earth, about 100 years ago... it our signals might have reached stars 100 light years away....
which isn't too far on the cosmic scale....

our galaxy is 100,000 light years in diameter

It would take 4.3 years for a radio signal to reach Alpha Centauri. Radio waves are a form of light, just with a much longer wavelength; they travel at the speed of light.

In the 1970's, a very elaborate radio signal was sent from Earth's largest radio telescope (Aricebo) toward the Hercules cluster (~25,000 light years away).

Radio travels at the speed of light, so approx. four years to Alpha Centauri. Radio and television signals have been traveling outwards from the Earth since the early part of the 20th century. We have received radio waves from quasars and pulsars, most of which are some of the most distant objects we can detect, billions of light-years away.

Alpha Centauri is about 4.37 light years from earth. Radio signals travel at the speed of light, so it would take about 4.37 years for radio signals to reach Alpha Centauri.

To answer the other portion of your question, yes we have attempted to send radio signals to other star systems. It's accepted that the first radio signals produced on earth to reach space were most likely produced in the first few years before world war II. Since then, countless radio waves have been projected into space from earth, both accidental and on purpose.

I hope they like "I love Lucy".

Television and radio signals actually decompose into static within one or two light years

Actually, it would've travelled a bit less than 100 light years. Radio signals weren't strong enough to transmit from Earth until the 1930s.

Just think, the first transmission ET will get from us is Hitler's speech at the Olympics in Germany... bad impression don't you think, with all the anti-Semitism going around?

LOL, anti-Semitism in an astronomy section... I am pro.