Hardware Gurus: How-to build passive Ethernet Hub?

Guys,

I have a setup where it's perfect, except I am short of 1 (one) TX100
port. I don't want to put in another switch/hub and for sure there
will be no further expansion to this (specialized) LAN.

I remember the ole COAX ethernet, everybody was on the same wire,
there was no need for a powered hub.

Can I just tie my TX100 wires together and create this one extra port?

I don't care about the extra collision, and the reduced bandwidth, and
my two CAT5s are less than 3 feet.

Does this work? Will I fry this thang?