I remember reading that declines in Analog TV meant that we did not send out as much of the sort of Signals SETI detects as we used to.
So I found this paper by the Contact Project on the topic and graphed the tables.
We produce far more Radio Frequency emissions than we used to but they are not in the way that stands out to classic SETI detections. The kind of narrowband signals (like a TV station being on one frequency) SETI looks for peaked around the analog TV era and has been declining since
Python mathplotlib code is here
by cavedave
3 Comments
mandatory [xkcd](https://xkcd.com/638/)
Unfortunately, except for very powerful and directed transmissions (such as the Arecibo message and radar like that at Goldstone for radar astronomy) our terrestrial radio signals will fall off to below what the Cosmic Microwave Background produces and be impossible to detect even with high-gain dish antennae even before they get to the closest stars.
Now plot something to indicate
Time and distance signal has spread and attenuation of signal by distance and increasing number if star systems within growing sphere of potential detection