Here is a quick little teaser image to see if anyone can guess what it is.
It actually has labels on it, but I obscured them to make it more of a challenge.
The pen is just to provide a clue about its size.

Here is a quick little teaser image to see if anyone can guess what it is.
It actually has labels on it, but I obscured them to make it more of a challenge.
The pen is just to provide a clue about its size.

I cannot find anything about 'Starlink 3800' nor the specific one that you have, but I found a "Kinamax IP-UGB20" that looks the same. No idea who the OEM was, everyone's rebadging everything, and most of the information about this seems to have been lost to time.
I think this "telephone adapter" is close enough to be called a winner. Both may be variants of Starlink 3800 VoIP Gateway.
The one I have is actually called a Telebox Personal VoIP Gateway. It has a PSTN line connector and a POTS telephone connector plus the USB connector. The indicators are for Power, PSTN and VoIP.
Congrats - here is your sleuthing award:

Wow, how did you know?
An external dial-up modem?
A network switch - as in "like a printer switch". On one network or the other. Can't be any crazier than the radar detector.
There are no wireless features....
Huge clue: The 2 other connectors are both RJ connectors....
Zigbee router/repeater?
RTC Modem ? Like a 56kbps one ?
Well that blew my guess of a radar detector. I guess wireless access point.