'TCL' are the initials of the person who created the first Ethernet transceiver
(Tat Lam).
https://books.google.com/books?id=ooBqdIXIqbwC&pg=PA73&lpg=PA73
He also sold the first 10mbit transceiver and repeater.
On 11/25/18 9:41 AM, Chuck Guzis via cctalk wrote:
Don't know the exact product, but TCL INc. was in
Fremont, CA and was a
maker of various bits of LAN gear.
--Chuck