VZX4X 1931

British Pirate on board a Tanker between California & the Orient!
It was almost impossible to obtain an amateur radio license aboard ships at this time. Some would make up a callsign and operate undercover.
Other known Pirate callsigns used from ships were BRJ, R5U, B4UP, S1R.

QSL NL7XM Collection
Info courtesy of N2BTD