The "hook up" is a holotape in the Fallout 76 update Wastelanders.
Location[]
The tape is received from Rose during Strange Bedfellows.
Transcript[]
When inserted into an emergency management system relay terminal at a relay tower:
-<--@ CONGRATULATIONS on NOT screwing this up!
-<--@ Now, prove you're not a moron and select
-<--@ "ACTIVATE TRANSMITTER CONNECTION"
-<--@ Failure to do so means you're an idiot.
-<--@ Hugs, kisses, 'n chems,
-<--@ ROSE
Activate Transmitter Connection[]
-<--@ Let the great HOOK UP begin!
-<--@ Boring stuff:
-<--@ ... finding connection.
-<--@ ... transmitting signal.
-<--@ ... return signal requested.
-<--@ ... connection verified!
-<--@ That's it! THE END!
-<--@ That thing you wanted to do is TOTALLY DONE.
-<--@ YOU'RE WELCOME.
-<--@ Now get your ass back to Top of the World
-<--@ and head for the Mezzanine before Meg beats
-<--@ you to it! Whatever's in there ain't going to
-<--@ want to babysit.
-<--@ P.S. YOU OWE ME ;)
When inserted into the Pip-Boy 2000 Mark VI or any other terminal:
>>>CONGRATULATIONS<<<
You obviously don't know how to follow directions, so here they are... AGAIN.
1. Find a RELAY TOWER
2. Put HOOK UP holo in RELAY TOWER TERMINAL (duh)
3. Select ACTIVATE TRANSMITTER CONNECTION
Failure to do results in me questioning why I even bother!
SMOOCHES!!!
-Rose