Portal field news

Portal field news

in ,

📱 | Ducati Monster AR experience new model, image confirmation on smartphone

Photo Ducati's "Monster Experience AR" logo

Experience the new Ducati Monster in AR and check the image on your smartphone

If you write the contents roughly
The excellent works will be released on Ducati's digital channel.

On May 5th, Ducati will be offering a digital experience "Monster Ex ..." on its official global website. → Continue reading


Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.

Channel (TV broadcasting)

tv setIn broadcastingChannel(English: television channel) Is TVBroadcasterorTelevision broadcasting networkPhysical assigned to eachTransmission lineOr a logical number to indicate them.Each frequency is assigned to the channel (= transmission line) indicated by each number.

However, in the Japanese context, the broadcaster or itsBroadcast program, Receiver (TV ortuner) Selectionswitch,Remote control key IDIndicates a broadcasting station, etc.numberIn some cases, the meanings such as are mixed.



In TV broadcasting in JapanVHF waveAs 1-12 channels,UHF waveThen 13-62 channels,SHF wave(For hard-to-view areas) is defined as 63-80 channels.Digital broadcastingAfter the technology was established, it is also called a physical channel.

Analog broadcastingIn, there is a one-to-one correspondence between the channel number of the receiver and the number assigned to the frequency band (frequency range).In the case of digital broadcasting, channel numbers 1 to 1 are assigned to each broadcasting in terrestrial broadcasting as in the case of analog broadcasting.Remote control key IDIt corresponds to a logical channel number (a number defined for performing operations and settings on the receiving device side) defined as (sometimes simply called an ID).The frequency band (physical channel) actually used in the broadcasts assigned these numbers is 13 to 52 channels, which is the same as that used in analog broadcasts.[1].Satellite broadcastingIn (BS digital broadcasting and CS digital broadcasting excluding BS analog broadcasting), the frequency band number (physical channel number) and each broadcasting do not have a one-to-one correspondence, and the same frequency band (physical channel) is used by multiple broadcasting stations. (Broadcaster) divides and uses.In this way, in digital broadcasting (terrestrial digital, BS digital, CS digital), the frequency band number actually used in broadcasting and the channel number operated by the receiver do not match at all.Details of the actual allocationTv frequency channelsSee.

The channel selection switch of the receiving broadcasting station on the receiving device (television or tuner) is also called a channel.Even after the switch shape has changed from the dial type to the button type, it is still generally used, but some manufacturers such as Sharp may have "channel selection".In addition, since there is generally a one-to-one relationship between the channel selection switch and the broadcast that can be viewed when operating with the receiving device, one broadcast is called a "channel" in addition to the meaning of the number assigned to the frequency band used for broadcasting. Also called.

In this way, the "channel" isTV stationIeBroadcasterSometimes refers to, but especially for satellite broadcastingConsignment broadcasterIs often referred to as a "channel" rather than a "television station."It has broadcasting equipmentCommissioned broadcasterIs due to the interpretation that is a TV station.

As mentioned above, strictly speaking, the "channel" of television broadcasting has several different meanings, so care must be taken not to confuse them in terms of usage and interpretation.

In the case of terrestrial broadcasting, the number of channels that can be viewed varies depending on the region.[2].

For example, centered on TokyoKanto regionIs broadcasting up to 12 channels (due to the broadcasting target area such as prefectural broadcasting under the Broadcasting Law, up to 9 channels can be received at the same time, and up to the case of receiving only the VHF antenna of analog broadcasting. 7 channels).Kansai regionOn average 8 channels (VHF for analog broadcasting is up to 6 channels),Hokkaido-Chukyo region-Okayama prefecture, Kagawa prefecture-FukuokaIn contrast to 7 channels (VHF has a maximum of 4 to 5 channels)Aomori-Toyama-San'in district-Kochi-OitaUp to 5 channels (NHK 2 channels + commercial broadcasters 3 channels), unless targeting waves outside the prefectureYamanashi-Fukui-MiyazakiThen, from the same point of view, up to 4 channels (NHK 2 channels + commercial broadcasting 2 channels),Tokushima-SagaThen, from the same point of view, there will be a maximum of 3 channels (2 NHK channels + 1 commercial broadcaster).

Correspondence between channel numbers and frequencies for TV broadcasting

  • 1 - 12Channel: VHF TV channel.
  • 13 - 62Channel: UHF TV channel.In addition, terrestrial digital television broadcasting is work (frequency summary,Digital Terrestrial Television Broadcasting in JapanSee) After completion13 - 52Use only channels.
  • 63 - 80Channel: SHF TV channel (for difficult-to-view areas. Allocated around 12GHz).
  • BS-1 --BS-23Channel (airborne wave for subscribers): Satellite broadcasting channel (12GHz band is assigned).
It is different from the frequency received by the tuner body.MoreTV frequency channel # 12GHz band (BS broadcasting)See.
  • C13 --C22Channel:CATVMidband channel.
  • C23 --C63Channel: CATV super high band channel.

Analog broadcastingIn, as a measure against interference, there is basically an agreement that adjacent channels should not be used in the same area and that the same channel should not be used in adjacent areas (example: in the Kanto region).2/5/7/9/11The channel was an empty channel).However, as an exception, channels 3 and 4 can coexist even if they are adjacent to each other because the frequency bands are separated (example:NHK E TeleTokyo Of3With channelsNippon TV Of4Channel).Also usuallyHorizontally polarizedFor terrestrial broadcastingVertical polarizationYou may be using adjacent channels by using[3]However, even in this case, the VHF7 channel and the VHF8 channel whose frequencies partially overlap cannot coexist.

In analog broadcasting, in some areas, it was shifted by ± 10kHz to prevent interference between broadcasting stations (offsetfrequency..For example, in the case of 1 channelCenter frequencyThere are several transmission stations that transmit at 92.99MHz, video frequency 91.24MHz, voice frequency 95.74MHz or center frequency 93.01MHz, video frequency 91.26MHz, voice frequency 95.76MHz).In addition, all frequencies of terrestrial digital television broadcasting are transmitted at the center frequency + 142.857kHz, but the offset frequency is not implemented.

For details on the correspondence between each channel number and frequency, seeTV Frequency Channel #Channel ListSee.


AmericaBecause of the large land area, it is not efficient to build a radio tower and distribute terrestrial waves, and cable TV has developed multi-channels.[4].


[How to use footnotes]

注 釈


  1. ^ Regarding the case where a part of analog broadcasting and the frequency used for digital broadcasting overlap in terrestrial broadcasting,Digital Terrestrial Television Broadcasting #Anaana ConversionSee.
  2. ^ In a broad sense, the interpretation of expressions such as "the number of broadcasts that can be viewed" and "viewing area" is based on the assumption that they can actually be physically received and viewed, but generally in a narrow sense. In many cases, it refers to the area assumed by the broadcasting station as the area to provide broadcasting and the general situation within the assumed area.Under the latter conditions, there are places where the broadcasts that are actually provided cannot be received due to geographical conditions, or where broadcasts in areas that are not originally expected to be received can be received.Therefore, it should be noted that the interpretation differs depending on the position in which the wording is used as a whole.
  3. ^ tvkSome relay stations etc.
  4. ^ Toshihiro Takagi "Smart TV and Video Business Who Designs Next-Generation Media?" 2012, Impress Japan, p. 55

Related item


Back to Top