To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

From Wikipedia, the free encyclopedia

CCIR System H is an analog broadcast television system primarily used in Belgium, the Balkans and Malta on the UHF bands.

Specifications

Some of the important specs are listed below.[1]

System G specifications
Frame rate Interlace Field rate Line/frame Line rate Visual b/w Vision mod. Preemphasis Sound mod. Sound offset Channel b/w
25 2/1 50[2] 625 15625[3] 5 MHz. AC3 neg. 50 μs F3 5.5 MHz. 8 MHz.
Channel spacing for CCIR television System H (UHF Bands)The separation between the audio and video carriers is 5.5 MHz.
Channel spacing for CCIR television System H (UHF Bands)
The separation between the audio and video carriers is 5.5 MHz.

A frame is the total picture. The frame rate is the number of pictures displayed in one second. But each frame is actually scanned twice interleaving odd and even lines. Each scan is known as a field (odd and even fields.) So field rate is twice the frame rate. In each frame there are 625 lines (or 312.5 lines in a field.) So line rate (line frequency) is 625 times the frame frequency or 625•25=15625 Hz.

The RF parameters of the transmitted signal are almost the same as those for System B which is used on the 7.0 MHz wide channels of the VHF bands. The only difference to the RF spectrum of the signal is that the vestigial sideband is 500 kHz wider at 1.25 MHz. Due to this and the extra width of the channel allocations at UHF, the width of the guard band between the channels is 650 kHz (assuming the worst case which is when NICAM sound is in use).

System G

Many countries use a variant of system H which is known as System G. System G is similar to system H but the lower (vestigial) side band is 500 kHz narrower. This makes poor use of the 8.0 MHz channels of the UHF bands by merely increasing the width of the guard-band by 500 kHz to 1.15 MHz. The advantage(?) is that the RF spectrum of system G (on UHF) is the same as system B (on VHF), simplifying the band-switching circuitry in VHF/UHF televisions.

See also

Notes and references

  1. ^ Reference Data for Radio Engineers, ITT Howard W.Sams Co., New York, 1977, section 30
  2. ^ Not an independent value: 25•2=50
  3. ^ Not an independent value: 25•625=15625

External links

This page was last edited on 28 July 2017, at 12:16
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.