Slow-Scan Television (SSTV)

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Slow-Scan Television (SSTV)
Robot 36waterfall.jpg
Frequencies 3 MHz,300 MHz
Frequency Range 3 MHz - 300 MHz
Mode USB
Modulation FM
ACF ACF is lpm value
Bandwidth 2.5 kHz
Location Worldwide
Short Description Slow-scan television (SSTV) is a method for picture transmission used by amateur radio operators to transmit and receive images.
I/Q Raw Recording Download file
Audio Sample

Slow-scan television (SSTV) is a method for picture transmission used by amateur radio operators to transmit and receive images. The most popular modes of SSTV are Robot, Scottie, and Martin.

A technical term for SSTV is narrowband television. Analog broadcast television requires at least 6 MHzMegaHertz (MHz) 10^6 Hz wide channels, because it transmits 25 or 30 picture frames per second (in the NTSC, PAL or SECAM color systems), but SSTV usually only takes up to a maximum of 3 kHzKiloHertz (kHz) 10^3 Hz of bandwidth. It is a much slower method of still picture transmission, usually taking from about eight seconds to a couple of minutes, depending on the mode used, to transmit one image frame.

SSTV uses analog frequency modulation, in which every different value of brightness in the image gets a different audio frequency. In other words, the signal frequency shifts up or down to designate brighter or darker pixels, respectively. Color is achieved by sending the brightness of each color component (usually red, green and blue) separately.


SSTV has been used in popular culture, including secret easter eggs in the video games Portal and Portal 2 by Valve.


Modes[edit]

Original Image:

BBC-Test.jpg





Robot[edit]

Description[edit]

SSTV Robot was developed by Robot Research Corporation. Used to send images over HFHigh Frequency (3-30 MHz) and VHFVery High Frequency (30-300 MHz) frequencies. The most popular modes in use today are Robot 36 and Robot 72.

Samples[edit]

Robot Modes
Robot 8 B/W Robot 12 B/W
Sample
Robot 8 BWsample.bmp
Robot 12 BWsample.bmp
Waterfall

Robot 8 BWwaterfall.jpg

Robot 12 BWwaterfall.jpg

Robot 24 Robot 36 Robot 72
Sample
Robot 24.bmp
Robot 36sample.bmp
Robot 72sample.bmp
Waterfall

Robot 24waterfall.jpg

Robot 36waterfall.jpg

Robot 72.jpg

Additional Images[edit]

Martin[edit]

Description[edit]

SSTV Martin was developed by Martin Emmerson, and was originally included as a ROM enhancement for Robot Research's SSTV units. Martin mode scans 256 lines instead of the standard 240. This is usually to give HAM operators 16px of banner room above or below their image for their callsign and other text. Martin is primarily used in Europe.

Samples[edit]

Martin Modes
Martin 1 Martin 2
Sample
Martin 1sample.bmp
Martin 2.bmp
Waterfall

Martin 1waterfall.jpg

Martin 2waterfall.jpg

Additional Images[edit]




Scottie[edit]

Description[edit]

SSTV Scottie was developed by Eddie Murphy GM3BSC, and was originally included as a ROM enhancement for Robot Research's SSTV units. Scottie mode scans 256 lines instead of the standard 240. This is usually to give HAM operators 16px of banner room above or below their image for their callsign and other text.

Samples[edit]

Scottie Modes
Scottie 1 Scottie 2 ScottieDX
Sample
Scottie 1sample.bmp
Scottie 2sample.bmp
ScottieDXsample.bmp
Waterfall

Scottie 1waterfall.jpg

Scottie 2waterfall.jpg

ScottieDXwaterfall.jpg

Additional Images[edit]




Decoding Software[edit]

Hobby Level Software

SSTV frequencies[edit]

Most common SSTV frequency is 14230 kHzKiloHertz (kHz) 10^3 Hz (USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables)). When this frequency becomes busy, some activity moves to 14227 or 14233 kHzKiloHertz (kHz) 10^3 Hz. During improved propagation conditions, amateur SSTV stations operate on 21340 and 28460 kHzKiloHertz (kHz) 10^3 Hz. SSTV transmissions from the International Space Station (ISSInformation Sending Station in an ARQ link (The station sending information to the recipient). Usually the signal that's longer in duration than the short RQ (Repeat Request) bursts from the IRS.) using callsing RS0ISS take place on 145800 MHzMegaHertz (MHz) 10^6 Hz (FMFrequency Modulation) in PD120 mode.

Video Examples[edit]

Additional Links[edit]