Not really. I was just hoping to provoke an informed and technical rant on the practical difficulties from @nixiebunny.
I was joking, nixiebunny, but your reply got me to thinking …
How do we know that ET doesn’t have their version of SETI? A version with the capability of signal filtering?
You have managed to discern TV signals from background noise even though you don’t think you have. Have you ever watched television without cable? 
I have indeed watched a TV set that received signals broadcast from a nearby transmitting antenna, using circuits that were designed to receive exactly those signals.
I have not figured out how one would do the same with signals from a distant planet orbiting a distant star, and presumably rotating on its axis, where said signals would be available a tiny fraction of the time due to said rotations, and extremely weak, and modulated using a completely unknown method at unknown frequencies and repetition rates.
YOU LUCKY, LUCKY BASTARD!
Ever been to the DMV?
The Atlanteans built a wall. The best wall.
Like I said, nixiebunny, we have no way of knowing what their level of tech is, though it would have to be comparable to out 1960’s to be able to receive those signals in the first place.
As I mentioned, SETI dos it and so its perfectly reasonable that there would be species out there who would do similar things.
SETI scans a whole range of frequencies. Their system is also very sensitive and can detect those low power transmissions. It isn’t much of a step to narrow that range of frequencies when a signal is detected (not sure, but I think SETI has that capability). A television is a further step along, where you can receive the specific signals transmitted on a specific frequency. And do so for multiple frequencies by using the channel changer. And don’t forget, we have had global television coverage since we started putting up satellites, so the signal would not be all that intermittent.
like this, you mean?
This guy…
…thinks that there aren’t any.
Well, yeah but…
You can’t pick up a signal that’s not being transmitted towards you. Global television coverage is not universal coverage. A typical TV transmitting antenna emits a flat plane of signal. This plane will intersect a distant planet for a brief time twice daily, due to the Earth’s rotation.
Satellite television is less useful for extraterrestrial detection, because its antennas are optimized to send 100% of the signals down to Earth, not into space. Go look up their antenna coverage patterns.
Furthermore, digital TV signals are pretty much indistinguishable from white noise on a spectrum analyzer.
All TV receivers are designed to receive exactly the type of signal that’s being sent to them. The range of possible frequencies and modulation patters is vast, which is why SETI spectrometers have millions of channels. They are operating under the hope that there’s some repetitive pattern to be detected somewhere.
But it takes a lot of resources to generate such signals, and commercial broadcasting is the only industry on Earth with the funding to do it (why would the military advertise its existence?) And as I’ve explained above, the TV industry is optimizing its transmissions so that no signal energy is ‘wasted’ by sending it to space.
Who knows what other civilizations would do in these circumstances.
Sorry, nixiebunny, but television, radio, the whole of the electromagnetic spectrum, radiates in a spherical manner, unless there are specific things to block the signal, such as a planet. As for optimizing the signal, yes, I agree, but not to that extent. There is always signal leakage.
I’ve always thought it incredibly egocentric to think intelligent life would bother with Earth at all.
I wouldn’t come here.
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