Edit: OK, so the story is definitely (at least partially) about aliens coming into contact with the Pioneer space probe.
I have a couple of short radio recordings of an acted Sci-Fi story (spoken in Serbian language). It was recorded at least 10 years ago, but the original recording is probably much older than that.
I would say the original recording is maybe from the 80s or even 70s. So the story must have been written at least ~25 years ago...just to give an idea.
Also, maybe it's from a synchronized cartoon (but it just sounds too good for a cartoon) or some TV show or maybe it was some sort of radio theater thing. I have no idea.
I translated some of it (the best I could).
Person 1: Look at the screen captain.
Person 2: It's clear that it's the work of sensible beings and that it's not a meteor. Don't panic. Our mission demands total secrecy. Unnecessary panic would just complicate the approach to the third planet of the solar system.
We must logically consider where that body is coming from.
Person 1: Based on everything known about that planet it could be said that it's some sort of higher degree of savagery.
Person 2: The thing is very suspicious. I don't think so, but everything's possible. Maybe it's a bomb?
Person 3: Maybe it's some sort of exercise?
Person 2: It's definitely not an exercise, that projectile is flying completely uncontrolled.
Person 1: I would like to make a suggestion. What about if we capture that [NOT CLEAR] and have a closer look at it.
Person?: Don't you think that might be dangerous? What if something's inside after all?
Person 2 or 3: That is correct. We could attract it with the magnetic field and then open it outside the ship.
Person ?: Scout, get to work!
Scout: Yes sir!
Person 1: Is there anything suspicious?
Person 2: Nothing so far. I have found some kind of primitive controlling device. [NOT CLEAR] must have come from somewhere outside. Probably from some rocket.
Person 1: What to you expect from those savages... Do continue.
Person 2: Some kind of board. It looks like an artistic attempt.
Person 1: Ha! An exhibition of primitive art is space, how foolish you are...Bring it here.
Person 1: This is the product of a culture that is showing a tendency of development. It's what we were like probably 100 000 generations ago.
Person 2: I would just like to know why they sent it to space at all. Does anyone understand what this drawing shows?
Person 1: If you would allow me to say something. This is a couple of [UNCLEAR] savages.
The man is raising his hand and that surely means: "We are poor savages and we have nothing. Come to our planet to give us things. That's why we sent our spacecraft, to call for you."
Person 2: That could be the correct interpretation. But how could have those poor uneducated savages known that we were coming? That proves that they are not so savage, that they have knowledge at their disposal which is respectful.
Person 3: I'm afraid that it's not a cry of a poor man, but something different.
Person 4: The bottom row is completely clear. It tells us that a spacecraft, coming from the third planet (counting from the center star), was sent our way. The message continues: "All of us, man and woman will defend our planet. Stop and don't approach us.". That is what the raised hand means, clearly. "We walk naked because everything we had we used to build machines with which we will destroy you."
Person ?: I'm sorry, but based on what do you conclude that they would destroy us?
Person 4: Based on the drawing on the upper left corner. The point from which the radial rays come from , that is without a doubt a symbol of explosion. Above that are the two conjoined circles. I don't think I'm far from the truth when I say that that is a sign of a threat, that they will break us in half with that explosion.