MMSSTV can be downloaded by clicking the following LinkĪnalogue SSTV transmissions can be found on HF frequencies around 3.640MHz LSB, 7.170MHz LSB, 14.230 MHz USB, 21.340MHz USB and 28.680MHz USB. The most commonly used program for Amateur SSTV transmission and reception is the dedicated SSTV program MMSSTV written by Makoto (Mako) Mori JE3HHT. MixW and DM780) have support built in for receiving SSTV pictures. Many digital-mode programs used for modes such as PSK and RTTY (i.e. The main modes of SSTV "encoding" in use include the AVT, Martin, Robot and Scottie modes. Analogue SSTV is governed by an "encoding scheme" that encodes or decodes the source image for transmission. A 1200 Hertz synchronization pulse is added so that lines can be correctly assembled at the receiver end. A transmission consists of horizontal lines scanned from left to right, building up an image progressively with each scan. Colour is achieved by sending the brightness of each colour component (red, green or blue) separately (Wikipedia - 12/7/11). The simplest recommended reception interface would include a 600:600 ohm isolation transformer from the speaker output to the line in on your PC.Īnalogue SSTV uses Analogue Frequency Modulation whereby each level of brightness in the source image gets modulated via a shift in frequency between 15Hz depending upon the brightness of the original image. All that is needed to transmit and receive SSTV is a good, stable sound card and audio lines in and out from your PC and radio.
The techniques for SSTV have improved quite considerably since those early techniques developed for the reception of signals from Space. In fact the first pictures of the Apollo 11 landing on the moon were actually transmitted by Slow-Scan techniques beaming a picture back to Earth at the rate of 320 lines at the rate of 10 frames per second.
Slow Scan Television (SSTV) is a narrow-band (voice spectra) picture transmission method used to receive and transmit static pictures via radio (Source: Wikipedia - 12/7/10).
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