Broadcast and cable communication systems

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Broadcast vs Cable network vs Online distributors

This page is about signal distribution and reception systems mainly focusing Cable TV and also broadcast communication network which is a system for transmitting audio and/or video content to a wide audience achieved through radio waves such as over-the-air broadcasting. These networks can be further categorized into different types such as Broadcast television systems and Radio broadcasting systems. Cable TV and cable networks uses a physical cable infrastructure to deliver signals to subscribers' homes, users need a subscription (see Early Online Services) and specific equipment (such as set-top box & STB) to access these signals. placeholder text

Simulators[edit]

Name Platform(s) Years(s) Region(s) Type(s) Enhancements Active Recommended
MyRetroTVs Web '50s, '60s, '70s, '80s, '90s, '00s United States of America Broadcast television systems
Cable network? 		~ ✓* ✓
swimelodeon Web '90s United States of America Cable network? ? ? ?

Comparison[edit]

MyRetroTVs
MyRetroTVs - 1996 news
This website is for watching captured footage from TV channels or various videos from the eras of the '50s to '00s, eliminates the need for handpicking videos and creating a personal collection, which can be time-consuming and require a significant amount of storage space. This website simply gathers videos from specific sources such as YouTube playlists etc, so we can say that this website offers a simulated experience of watching TV channels from during those specific eras. It also supports some basic #Enhancements. While this is a great way to experience retro television, there's room for even deeper immersion. For example adding surfing channel collections playlists, this could be achieved by integrating with Archive.org's vast collection of VHS TV channel surfing captures. Also integration with EmuVR, perhaps with some kind of support for playlists support for libretro core, could be a great next step too.
swimelodeon
This website is for watching '90s Nicktoons, original Adult Swim, old-school cartoons and anime. placeholder text

Enhancements[edit]

Name MyRetroTVs
Post-Processing Filters ✓
AI-powered filter compatible
(Freestyle) 		?
Shader Chain ~*
Inverse tone mapping compatible ?
Quality of life Rewind ?
Fast-Forward/Turbo Speed ?
Savestates ?
Video recording ?
User Profile ✗
Command Line Options ?
Built-in Custom resolution/CRTSwitchRes
For using this on Windows OS you need CRT Emudriver.
Another option is using EDID editor tool such as "Custom Resolution Utility". 		Exclusive to libretro cores and GroovyMAME at the moment.
Also there is a project for achieving software emulators like libretro cores and GroovyMAME send the raw RGB data over a network to a core running on MiSTer, it basically turns the MiSTer into a GPU for the emulator allowing for easy setup and use with CRT TVs/Arcade monitors.
Big Picture Mode ?
Misc Netplay or SyncPlay ?
AI Service
With the help of OCR and other techniques, the AI service can provide a live translation of a video, or text-to-speech capabilities for the visually impaired among other things, either on demand or automatically. 		Exclusive to libretro cores at the moment. So there is no support at the moment.
EmuVR support Exclusive to libretro cores at the moment. So there is no support at the moment.

Type(s)[edit]

Broadcast television systems[edit]

Analog Television Systems

During the 1st and 2nd generation of video game consoles, RF connection was the only way to connect a video game console to a TV. During the 3rd generation some consoles such as the NES had separate outputs for unmodulated signals and all consoles had the option by the 4th generation. By the 5th generation, composite video became the standard form of connecting a video game console

NTSC
NTSC was the first color television system to be widely adopted, NTSC works by transmitting a high frequency color signal on top of the legacy black and white image, the amplitude of this signal determines the saturation while the phase determines hue, this is a property that many early consoles and home computers took advantage of. Every nation using the NTSC system also used a 59.94hz field rate. Many filters exist to replicate this display on emulators.
PAL
PAL was created in Germany as a response to NTSC's susceptibility to hue fluctuations during poor reception conditions. The difference from NTSC is that the phase is inverted every other line, causing phase errors to cancel out, causing a less objectionable drop in saturation instead. The color signal is also in a higher frequency than NTSC, thanks to the larger channel bandwidth on European channel allocations. PAL was almost always used with a 50hz field rate.
PAL-M
PAL-M was only used in Brazil and should not be confused with PAL-60. PAL-M uses PAL encoding on NTSC channel allocations, as such the frequency of the color signal is lower than that of regular PAL, close but not the same as NTSC. As with NTSC PAL-M used a 59.94hz field rate.
SECAM
SECAM (also written as SÉCAM ) was developed in France for similar reasons as PAL. Unlike NTSC and PAL, which transmits a full color signal each line, SECAM alternates between two axes of the color signal, making a delay line mandatory for decoding (hence the name which translates roughly as Sequential color with memory). Also unlike NTSC and PAL this signal is frequency modulated, which makes it more robust to transmission errors. Aside from France, SECAM was used by the Soviet Union and its satellite states. For this reason SECAM is rarely found on video game consoles, most often opting to use a RGB SCART cable instead (in some cases such as the NES, the RGB signal comes from an internal PAL decoder, hence not being "pure" RGB). Rare exceptions are the French Atari 2600 and Soviet Sega Master System
MUSE
MUSE (Multiple sub-Nyquist Sampling Encoding), also known commercially as Hi-Vision (high definition television) was created in Japan in the eighties where it was used for HDTV transmissions as well as laserdisc. MUSE works in a completely different manner from the above systems and was never used for any video game console, and is only mentioned here as it was still an analog system :)
Samples

Comparison table[edit]

System Refresh rate Chroma subcarrier frequency Usage Effect of phase errors
NTSC 59.94 3.58 MHz Most of the Americas, South Korea, Japan, Taiwan Color shifts
PAL 50 4.43 MHz Most of Europe, Australia, New Zealand Desaturation
PAL-60 59.94 4.43 MHz 60Hz modes in PAL regions, never used in broadcasting Desaturation
PAL-M 59.94 3.58 MHz Brazil Desaturation
SECAM 50 France Immune

Recordings of Broadcast Television[edit]

Early TV was broadcast live. Different means were invented for recording a broadcast.

Professional formats
Telerecordings, also known as Kinescopes, were means of recording a television program onto film. In 50hz territories, the film ran at 25fps and was synchronised with the image being drawn on a CRT. The image was slightly defocused to avoid recording a scanline structure, as that would beat against scanline structure of the telecine (a device used for transferring film to video) causing moire. Telerecordings were always in black and white, as the shadow mask used on color CRTs would cause moire when superimposed on the grain structure of color film. However, some telerecordings were made without filtering out the PAL subcarrier, which allowed modern methods to recover the "buried" color signal.
Quadruplex by Ampex was the first commercially successful format for recording video, released in 1956. Because a video signal requires significantly higher bandwidth than audio, and the tape speed needed for achieving such a bandwidth was impractical to achieve with linear recording (such as on an audio tape). The solution was to have a set of four magnetic heads rotating as 2 inch tape passed by them, hence the name Quadruplex, as a result the effective tape speed was over 1500 ips, or 100 times the linear tape speed. Audio was still recorded linearly. As technology progressed, smaller less cumbersome format took its place.
Sony's U-matic, released in 1971, was the first video format to store the tape inside a cassette instead of on a reel that required manual threading. While it never caught on as a home format due to its high price, it became popular for industrial and educational use. It also found significant use in newsgathering.
Home formats
While home video recording remained out of reach for two decades, home audio recording was a different matter. A number of otherwise lost programs exist in audio form due to watchers recording their favorite shows onto audio tapes, often by simply putting a microphone near the TV's speaker. More inventive persons would tape the audio signal electronically from the TV.
Several home video formats came out in the 1970s, however the two most important ones were Sony's Betamax (not to be confused with Betacam, which was a later professional format) and JVC's VHS in 1975 resp. 1976. While Betamax had a headstart, VHS came out victorious.

Radio broadcasting[edit]

In terrestrial radio broadcasting the radio waves are broadcast by a land-based radio station, while in satellite radio the radio waves are broadcast by a satellite in Earth orbit.

Analog terrestrial radio uses amplitude modulation (AM) or frequency modulation (FM). AM is the older technology and works by varying the amplitude (strength) of the carrier according to the sound being broadcast. FM was developed later in response to the shortcomings of AM, and instead has a constant amplitude while varying the frequency of the carrier, making the signal more robust at the expense of requiring a larger bandwidth. For that reason FM is always used on the VHF band (between 30 and 300 MHz, typically 87.5-108 MHz is used for FM radio)

There are preservation efforts by Radio Preservation Task Force, National Recording Preservation Board and Association of Recorded Sound Collections dedicated to project operates in fulfillment of the “to develop an online inventory of extant American radio archival collections.” Over 2000 radio collections are linked in this database and more to come. Also see radio collections on Archive.org.

Teletext[edit]

Zxnet's teletext viewer

Emulation[edit]

Name Active Recommended
zxnet ✓ ✓
Teletext-capable version of JSBeeb ? ~
PagesFromCeefax ? ~

See also[edit]

Home media or media content playback focused devices

External links[edit]

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