page_title: Radiofax
section_title: Weatherfax
hierarchical_section_title: Radiofax / Weatherfax
caption_attribution_description: English: A marine radio fax news from Tokyo Radio JJC Station received using MIXW with a SSB HF communication receiver
context_page_description: Radiofacsimile, radiofax or HF fax is an analogue mode for transmitting monochrome images via high frequency radio waves. It was the predecessor to slow-scan television. It was the primary method of sending photographs from remote sites from the 1930s to the early 1970s. It is still in limited use for transmitting weather charts and information to ships at sea.
context_section_description: A decade after the introduction of radiofax National Weather Service (NWS) began transmitting weather maps using the radiofax technology. The NWS named this new service weatherfax (portmanteau word from the words "weather facsimile") The cover of the regular NOAA publication on frequencies and schedules states "Worldwide Marine Radiofacsimile Broadcast Schedules". 
  Facsimile machines were used in the 1950s to transmit weather charts across the United States via land-lines first and then internationally via HF radio. Radio transmission of weather charts provides an enormous amount of flexibility to marine and aviation users for they now have the latest weather information and forecasts at their fingertips to use in the planning of voyages. 
  Radiofax relies on facsimile technology where printed information is scanned line by line and encoded into an electrical signal which can then be transmitted via physical line or radio waves to remote locations. Since the amount of information transmitted per unit time is directly proportional to the bandwidth available, then the speed at which a weather chart can be transmitted will vary depending on the quality of the media used for transmission.
  Today radiofax data is available via FTP downloads from sites in the Internet such as the ones hosted by the National Oceanic and Atmospheric Administration (NOAA). Radiofax transmissions are also broadcast by NOAA from multiple sites in the country at regular daily schedules. Radio weatherfax transmissions are particularly useful to shipping, where there are limited facilities for accessing the Internet.
  The term weatherfax was coined after the technology that allows the transmission and reception of weather charts (surface analysis, forecasts, and others) from a transmission site (usually the meteorological office) to a remote site (where the actual users are).
caption: A marine radio fax news from Tokyo Radio JJC Station received using MIXW with a SSB HF communication receiver.
exif: {}