New Zealand Herald, 16 May 1934, p 13
COAST RADIO STATIONS
CHANGE IN CALL SIGNS
[BY TELEGRAPH—PRESS ASSOCIATION]
Consequent on the adoption of radio communication regulations, call signs for the Cape Maria Van Diemen radio beacon and other coastal stations have been altered. The Cape Maria call, ZLN, will be changed to ZMZ as from July 1, and from the same date the Dominion Observatory call sign will be amended to ZMO, and the Gisborne Harbour Board station to ZMQ.