What would a orbital station and activity look like from the ground?

The Setup:

We have a highly advanced orbital station. It is designed to be rather stealthy, like a observation post.

Is it possible to make it completely invisible to the naked eye, even when in low-earth orbit?

Now to the hard part:
Computers or similar mechanisms on the ground are controlled by the station by short, rare bursts of commands.
How would I explain, that this information transfer is visible for a short window of time, even though the station is highly advanced. I need this transfer events to be noticeable from the surface for plot-related reasons.

Or is the fact, that you can see the commands, entirely improbable?

Clarifications:

Yes, the communication should be noticeable from the ground, while the station remains hidden, and trigger a search for it.

The method of the people on the ground are the naked eye, maybe a radio. Telescopes etc. are planned for later, but only after the existence of the station has been indicated by the communications.

posted over 7 years ago

System‭

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