I'm reading the Goddard Space Flight Centre's guide to using the STDN (Spaceflight Tracking and Data Network), of which the Orroral Valley Tracking Station was a part. It was written in 1974, when the network had been in existence for about 15 years or so. (In fact it's getting quite hard to work out the divisions between the networks - DSN, MSFN, STADAN, STDN, etc).
(And there is an antenna called SATAN).
I've never thought about what USB stands for before. But the following quote from the STDN User's Guide suggests that this is its origin:
The two 9-meter telemetry antennas (BDA and VAN) are receive only in the 2200- to 2300-MHz and 225- to 260-MHz bands and the 4.3- meter antenna (WNK) receives in the 400- to 402-MHz band. The 4.3-meter, 9-meter, and 26-meter Unified S-band (USB) antennas have both transmit and receive capability but receive only the 2200- to 2300-MHz band. (The terminology USB derived from
the fact that multiple support functions may be accomplished by this single "unified" system).
Goddard Space Flight Centre 1974 STDN User’s Guide Baseline Document. Revision 2. NASA-TE-X-72932 p 1-4