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Slow Scan TV - pictures over radio


SSTV usually only takes up to a maximum of 3 kHz 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.

Since SSTV systems operate on voice frequencies, amateurs use it on shortwave (also known as HF by amateur radio operators), VHF and UHF radio.


SSTV uses analogue 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. Colour is achieved by sending the brightness of each colour component (usually red, green and blue) separately. This signal can be fed into an SSB transmitter, which in part modulates the carrier wave. (There is also a digital SSTV mode - details at a later time.)


There are a number of different modes of transmission, but the most common ones are Martin M1 (popular in Europe) and Scottie S1 (used mostly in the USA). Using one of these, an image transfer takes 114 (M1) or 110 (S1) seconds. Some black and white modes take only 8 seconds to transfer an image.


Using a receiver capable of demodulating single-sideband modulation, SSTV transmissions can be heard on the following frequencies:



Band Frequency Sideband
80 meters 3845 kHz (3730 in Europe) LSB
40 meters 7170 kHz (7165 in Europe) LSB
20 meters 14,230 kHz USB
15 meters 21,340 kHz USB
10 meters 28,680 kHz USB
11 meters 27,700 kHz (Pirate Radio) USB


Regular reception on 14230kHz and 14233kHz




Software for PC (Windows) MMSSTV (TX and RX) go here MMSSTV site


Receive only RX-SSTV site


For Linux QSSTV go here Multiscan site


MultiScan 3B is an Application for Ham Radio Slow Scan TV (SSTV) Communications. It is built to run on
Mac OS X 10.6 or later versions. Go here qsl.net


If you have not got an HF receiver then use the Web HF receiver  you can use the audio for the windows programs - no info on other  operating systems, you use the STEREO MIX part of the audio mixer on your computer. For XP users STEREO MIX is normally included in your system.


Needs HTML5 or Java and best with Firefox or Chrome.


For Windows 7 and 8 you may need a virtual cable, have a look here RTL-SDR Cable site or if your audio is a Realtek HD device then on their website you can download the driver that gives STEREO MIX, go here realtek.com.tw High Definition Codecs.


If you have an Android device you could use DROID-SSTV - tested with a HUDL, using the microphone in front of speaker, or using Firefox and the mobile version of the  WEB receiver.




Download/Listen MP3 audio file of above picture


If you download the MP3 and play it whilst running MMSSTV then you should get the same image.



Below are some received pictures using the Web HF receiver and MMSSTV on an XP computer.



See the Youtube video at the bottom of this page.








Ensure you have your speakers are on to hear the audio.


Volume level can be changed - mouse over video and change as required using scale next to speaker icon.


Audio starts about 5 seconds in.