본문
What is 22kHz and What is DiSEqC ?
In order to squeeze more channels into a given frequency band width, channels are transmitted with vertical OR horizontal polarisation. (It doesn't matter what the word means, just accept it).
The conventional LNB known as the "Marconi (polarisation) Switching LNB" responds to the supply voltage to change the polarisation. If the supply voltage going up the dish cable is less than 15 volts, the LNB will "see" only vertically polarised transmissions. If the voltage is more than 15 volts, it will "see" only horizontally polarised transmissions.
The older type of LNB had a separate polariser to do this job and was able to use the voltage to select High Band or Low Band operation (by changing the internal oscillator frequency).
So the modern LNB has a problem if it has to switch between two frequency bands. The problem was overcome with the introduction of the "Universal" LNB.
The "Universal" LNB switches polarisation with voltage but it also switches its internal oscillator for "High Band" when it "hears" a 22kHz tone. Specificallly, the oscillator changes from 9.75 GHz to 10.6 GHz.
Recently manufactured receivers incorporate a 22kHz tone generator which is menu-selectable on a per-channel basis. (One exception is the Ferguson SRD6 which has a tone generator but no menu selection. The tone comes on automatically if you program a channel for a higher frequency).
Older receivers require an external tone generator box in order to make the "Universal" LNB select High Band. The external box can be controlled by a manually operated switch or by some feature of the receiver which will put a voltage onto its control wire to switch it on.
An alternative use for the 22kHz tone is to control an external switching box whichfeeds signals from one of a pair of LNBs into the receiver. For example, you could have two separate LNBs on a dish connected to a switching box which is itself connected to the receiver by a single coaxial cable. When the box "hears" a 22kHz tone it swaps to the other LNB.
Digital Satellite Equipment Control (DiSEqC) is an extension of this idea. It relies on a switching box which detects the 22kHz tone pulsing rapidly on and off. In this way, a specially designed receiver can control numerous LNBs through a DiSEqC switching box.
For a more comprehensive discussion of DiSEqC, read "What Satellite TV" magazine March 1997 issue and "TELEVISION servicing" magazine, November 1997 issue.
* DiSEqC 에 대한 상세 자료는 http://www.utelsat.com 을 참조 하시면 많은 도움이 될 것입니다.
* DiSEqC 1.0과 2.0 은 분배기 혹은 멀티스위치처럼 생긴 장비이며, 같은 범주로 묶을 수 있으나, DiSEqC 1.2 는 스위치가 아니라, DiSEqC 1.2 모터라고 불립니다. 이것은 외형적으로 기존 1.0이나 2.0과는 완전히 다르기 때문입니다. 그럼에도 DiSEqC 이라 불리는 것은 UTELSAT의 DiSEqC 기술, 개념이 응용되었기 때문입니다. 그리고, DiSEqC 2.0 스위치에도 일반적 스위치와 멀티스위치로 분류되며, 멀티스위치도 CASCADE, 즉 계단식 설계를 지원하는 스위치도 있습니다. 물론 수신기의 올바른 환경설정 역시 대단히 중요합니다.
* 대략적인 개념은 위의 영문으로 충분할 것이나, 상세한 내용은 유텔샛 홈페이지의 기술문서를 참조하셔야 하며, 본인 역시 유텔샛의 기술문서를 정독하지 않았기에, 상세 답변은 곤란합니다.
* 개발자는 유텔샛의 기술문서를 반드시 읽어야 할 것이며, 설비 엔지니어는 위의 문서만으로 충분합니다.
--- 양승한님 작성글 입니다. ---
diseqc을 보면
diseqc1.0 diseqc1.1 diseqc1.2 ....... diseqc2.0
이렇게 각각 종류들이 있던데
이것들에 차이는 무엇인가요?
궁금하네요. 알려주세요~~
In order to squeeze more channels into a given frequency band width, channels are transmitted with vertical OR horizontal polarisation. (It doesn't matter what the word means, just accept it).
The conventional LNB known as the "Marconi (polarisation) Switching LNB" responds to the supply voltage to change the polarisation. If the supply voltage going up the dish cable is less than 15 volts, the LNB will "see" only vertically polarised transmissions. If the voltage is more than 15 volts, it will "see" only horizontally polarised transmissions.
The older type of LNB had a separate polariser to do this job and was able to use the voltage to select High Band or Low Band operation (by changing the internal oscillator frequency).
So the modern LNB has a problem if it has to switch between two frequency bands. The problem was overcome with the introduction of the "Universal" LNB.
The "Universal" LNB switches polarisation with voltage but it also switches its internal oscillator for "High Band" when it "hears" a 22kHz tone. Specificallly, the oscillator changes from 9.75 GHz to 10.6 GHz.
Recently manufactured receivers incorporate a 22kHz tone generator which is menu-selectable on a per-channel basis. (One exception is the Ferguson SRD6 which has a tone generator but no menu selection. The tone comes on automatically if you program a channel for a higher frequency).
Older receivers require an external tone generator box in order to make the "Universal" LNB select High Band. The external box can be controlled by a manually operated switch or by some feature of the receiver which will put a voltage onto its control wire to switch it on.
An alternative use for the 22kHz tone is to control an external switching box whichfeeds signals from one of a pair of LNBs into the receiver. For example, you could have two separate LNBs on a dish connected to a switching box which is itself connected to the receiver by a single coaxial cable. When the box "hears" a 22kHz tone it swaps to the other LNB.
Digital Satellite Equipment Control (DiSEqC) is an extension of this idea. It relies on a switching box which detects the 22kHz tone pulsing rapidly on and off. In this way, a specially designed receiver can control numerous LNBs through a DiSEqC switching box.
For a more comprehensive discussion of DiSEqC, read "What Satellite TV" magazine March 1997 issue and "TELEVISION servicing" magazine, November 1997 issue.
* DiSEqC 에 대한 상세 자료는 http://www.utelsat.com 을 참조 하시면 많은 도움이 될 것입니다.
* DiSEqC 1.0과 2.0 은 분배기 혹은 멀티스위치처럼 생긴 장비이며, 같은 범주로 묶을 수 있으나, DiSEqC 1.2 는 스위치가 아니라, DiSEqC 1.2 모터라고 불립니다. 이것은 외형적으로 기존 1.0이나 2.0과는 완전히 다르기 때문입니다. 그럼에도 DiSEqC 이라 불리는 것은 UTELSAT의 DiSEqC 기술, 개념이 응용되었기 때문입니다. 그리고, DiSEqC 2.0 스위치에도 일반적 스위치와 멀티스위치로 분류되며, 멀티스위치도 CASCADE, 즉 계단식 설계를 지원하는 스위치도 있습니다. 물론 수신기의 올바른 환경설정 역시 대단히 중요합니다.
* 대략적인 개념은 위의 영문으로 충분할 것이나, 상세한 내용은 유텔샛 홈페이지의 기술문서를 참조하셔야 하며, 본인 역시 유텔샛의 기술문서를 정독하지 않았기에, 상세 답변은 곤란합니다.
* 개발자는 유텔샛의 기술문서를 반드시 읽어야 할 것이며, 설비 엔지니어는 위의 문서만으로 충분합니다.
--- 양승한님 작성글 입니다. ---
diseqc을 보면
diseqc1.0 diseqc1.1 diseqc1.2 ....... diseqc2.0
이렇게 각각 종류들이 있던데
이것들에 차이는 무엇인가요?
궁금하네요. 알려주세요~~
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