World Library  
Flag as Inappropriate
Email this Article

CCIR System M

Article Id: WHEBN0023845511
Reproduction Date:

Title: CCIR System M  
Author: World Heritage Encyclopedia
Language: English
Subject: 441-line television system, VIT signals, NTSC, Frequency offset, CCIR System H
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

CCIR System M

Radio spectrum of a System M television channel with NTSC color

CCIR System M, sometimes called 525 line, is the analog broadcast television system used in the United States since July 1, 1941, and also in most of the Americas and Caribbean, South Korea, and Taiwan. Japan uses System J, which is nearly identical to System M. The systems were given their letter designations in the ITU identification scheme adopted in Stockholm in 1961. Both System M and System J display 525 lines of video at 30 frames per second using 6 MHz spacing between channel numbers, and is used for both VHF and UHF channels.

Specifications

World television systems
System Lines Frame rate Channel b/w Visual b/w Sound offset Vestigial sideband Vision mod. Sound mod. Notes
J 525 30
(29.97 NTSC)
6 4.2 +4.5 0.75 neg. FM Japan (NTSC-J)
M 525 30
(29.97 NTSC)
6 4.2 +4.5 0.75 neg. FM Most of the Americas and Caribbean; Philippines, South Korea, Taiwan (all NTSC-M)
Brazil (PAL-M)

Color standards

Television color encoding by nation; Brazil (PAL-M) and all green countries (NTSC) are based on monochrome System M.

NTSC-M and NTSC-J

Strictly speaking, System M does not designate how color is transmitted. However, in nearly every System M country, NTSC is used for color television, a combination called NTSC-M, but usually referred to more recently as simply "NTSC" because of the relative lack of importance of black-and-white television. In NTSC-M and Japan's NTSC-J, the frame rate is offset slightly, becoming 30000/1001 frames per second, usually labeled as the rounded number 29.97.

PAL

The main exception to NTSC is Brazil, where PAL color is used instead, resulting in the PAL-M combination unique to that country, which is monochrome-compatible with other System M countries, but not compatible with other PAL countries, which use different basic systems as their base. PAL-M signals are at 30 frames per second instead of slowing down to 29.97 like NTSC.

See also

  • NTSC — dominant color system used with System M, so much so that System M is often referred to as "NTSC". Much of the information in the NTSC article is actually about System M.
  • Broadcast television systems — explains other types of television system standards
  • Multichannel television sound — usual method for adding stereo to System M audio
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.