====== Amateur TV (ATV) ======

Amateur Television (ATV) is a mode of communication in amateur radio that focuses on transmitting video and audio signals. It is used by amateur radio operators to experiment with television technologies, broadcast live video, or share pre-recorded content over designated amateur radio frequencies.

ATV combines traditional television technology with amateur radio operations, offering a unique way for operators to share information visually.

===== Overview =====

ATV is typically transmitted in two formats:
  - **Analog ATV**: Similar to conventional broadcast TV, using AM (Amplitude Modulation) for video and FM (Frequency Modulation) for audio. Common analog formats include NTSC, PAL, or SECAM.
  - **Digital ATV (DATV)**: Uses modern digital encoding technologies like MPEG-2 or MPEG-4, offering better image quality and reduced bandwidth usage compared to analog.

ATV signals are usually transmitted on UHF or microwave bands due to the bandwidth requirements. However, lower frequency bands like VHF may also be used for short-range transmissions.

===== Uses of ATV =====

Amateur TV serves various purposes in the amateur radio community:
  - **Technical Experimentation**: Testing and improving video transmission technologies.
  - **Emergency Communications**: Sharing visual information in disaster response scenarios.
  - **Public Service Events**: Broadcasting live video from community events, marathons, or parades.
  - **Amateur Collaboration**: Allowing hams to visually communicate or demonstrate technical setups.

===== ATV Frequencies =====

ATV operates on amateur radio frequencies allocated for wideband use. These vary by region, but commonly used bands include:
  - **70 cm Band (420-450 MHz)**
  - **33 cm Band (902-928 MHz)**
  - **13 cm Band (1240-1300 MHz)**
  - **3 cm Band (10 GHz)**

Operators should refer to their local frequency allocation charts to ensure compliance with regional regulations.

===== Equipment for ATV =====

To operate ATV, the following equipment is typically required:
  - **Transmitter**: Capable of encoding and sending video/audio signals.
  - **Receiver**: A compatible receiver or set-top box to decode ATV signals.
  - **Antenna**: Suitable for the operating frequency and desired range.
  - **Camera/Video Source**: For capturing video content.
  - **Modulator/Demodulator**: Converts signals between baseband and RF for transmission and reception.

===== Digital ATV (DATV) Advantages =====

Digital ATV (DATV) offers several advantages over analog ATV:
  - **Improved Image Quality**: High-definition video with less noise or interference.
  - **Lower Bandwidth Usage**: Efficient encoding reduces the frequency space required.
  - **Interoperability**: Easier integration with modern broadcasting equipment and software.
  - **Error Correction**: Enhanced reliability through error correction protocols.

===== Challenges of ATV =====

ATV also comes with some challenges:
  - **High Bandwidth Requirements**: ATV signals require significantly more spectrum compared to voice or data transmissions.
  - **Equipment Costs**: ATV requires specialized equipment, which may be expensive.
  - **Propagation Limitations**: Like other high-frequency signals, ATV is affected by line-of-sight propagation and terrain obstructions.

===== ATV on RepeaterBook =====

Repeaters with ATV capabilities can be listed on **RepeaterBook**. The repeater's details page includes:
  - Operating frequency
  - Bandwidth (analog or digital)
  - Transmission format (e.g., NTSC, MPEG-2)
  - Input and output modes

===== Related Links =====
  * [[https://www.repeaterbook.com/repeaters/niche/index.php?mode=ATV|RepeaterBook ATV Directory]]
  * [[https://www.batc.org.uk/|British Amateur Television Club (BATC)]]
  * [[https://www.arrl.org/amateur-television|ARRL Amateur Television]]
  * [[https://www.atco.tv/|Amateur Television Network (ATN)]]