During the 1980–1990 period, maritime radio surveys underwent significant transition, moving from traditional manual Morse code and voice systems toward more automated, digital, and satellite-based technologies. This era was characterized by the phasing in of the Global Maritime Distress and Safety System (GMDSS) requirements, which revolutionized how vessel safety and communication equipment were inspected.

Key aspects of maritime radio surveys and technology between 1980 and 1990 included:

Technological Shifts and Surveys

• Transition to GMDSS: The 1980s saw the development and early adoption of GMDSS, which shifted focus from operator-dependent communication to automated systems like Digital Selective Calling (DSC).

• VHF Channel Changes: In 1979, new VHF channels (60-88) with 25 kHz spacing were introduced to replace older, wider spacing, with full conformity required by 1983.

• Equipment Upgrades: The late 1980s saw the introduction of more sophisticated equipment, such as Harris Exciter units in transmitting sites.

• Survey Focus: Inspections moved from testing purely manual equipment to verifying the readiness of automated distress signaling devices.

  GMDSS Testers +4

Regional and Operational Examples (NZ Context)

• New Zealand Coastal Stations: During the 1980s, New Zealand's coastal radio stations (e.g., Himatangi Radio) operated a mix of older valve-based, 40kW, and newer, 15kW PEP Harris solid-state transmitters.

• Land Mobile Surveys: In 1980, surveys were conducted to check receiver sensitivity and transmitter power output for various land mobile channels.

• Equipment Maintenance: Technicians in this period were heavily involved in maintaining and surveying a wide range of radio equipment, from older heterodyne synthesizers using transistors to newer solid-state units.

Regulatory Context

• SOLAS Convention: The Safety of Life at Sea (SOLAS) convention, Chapter IV, provided the international framework for these surveys, emphasizing the need for accurate, functional radio, and navigation equipment.

• Survey Frequencies: Surveys included initial, annual, and periodical inspections to ensure compliance with international regulations.

By 1990, the groundwork for the mandatory GMDSS implementation, which officially began in 1992, was well established, with surveys focusing heavily on the new digital capabilities of maritime radio equipment.