Tagged: SSTV

The International Space Station is Transmitting SSTV Images

Happysat, a reader of RTL-SDR.com has written in to remind us that the International Space Station (ISS) is currently transmitting slow scan television (SSTV) images out of respect of the 80th birthday of Russian cosmonaut and first man to go to space Yuri Gagarin. The images will be transmitted continuously until 24 February 21.30 UTC.

SSTV is a type of radio protocol that is used to transmit low resolution images over radio. A RTL-SDR dongle and satellite antenna (QFH, turnstile, even terrestrial antennas like random wire antennas and monopoles have been reported to work) can be used to receive and decode these images. Happysat writes that it is expected that the ISS will continuously transmit 12 images at a frequency of 145.800 MHz FM using the SSTV mode PD180, with 3 minute off periods between each image.

To decode the images it is recommended to use SDR# and pipe the audio into MMSSTV, a freeware SSTV decoding software program. To get the best results out of MMSSTV happysat recommends enabling “Auto slant” and “Auto resync” under Options->Setup MMSTV->RX.

To know when the ISS is overhead you can track it online using http://spotthestation.nasa.gov/sightings/, http://www.isstracker.com/ or http://www.mcc.rsa.ru/English/trassa.htm.

Received SSTV images can be submitted to the ARISS Gallery, and Happysat has also uploaded a collection of his own personal received images here.

Happysat also shows us some images from the ISS showing the Kenwood D710 transceiver located in the Russian service module, the computers used to generate the SSTV signal and the antennas used for amateur radio transmission.

One of the broadcast SSTV images from the ISS
One of the SSTV images broadcast from the ISS
Computers on the ISS used to transmit SSTV images
Computers on the ISS used to transmit SSTV images
Antennas on the ISS used to transmit SSTV images
Antennas on the ISS used to transmit SSTV images

Listening to SSTV from the ISS with an RTL-SDR

On December 18 and 20 the International Space Station transmitted several SSTV images to celebrate what would have been the 80th birthday of Yuri Gagarin who was the first human to orbit the Earth. SSTV stands for Slow Scan Television and is a method for sending small low resolution images over radio.

Over on YouTube several RTL-SDR users captured these images. UltraTechie shows a video where he captures the SSTV image using a portable set up consisting of a Windows 8 tablet running SDR#. He used a handheld 3 element 2m Yagi antenna to tune into the 145.8 MHz signal. UltraTechie writes that he also used an LNA, but that it was probably not required as the signal was quite strong.

ISS SSTV reception on a portable setup using RTL-SDR

Another YouTube user Tom Mladenov shows another video where the SSTV image is received. Tom used a QFH antenna.

Receiving Mexican Pirate SSTV on Military Satellite Frequencies with the RTL-SDR

Happysat, a reader of RTL-SDR.com wrote in to let us know his experience with receiving Milsat pirate SSTV images using his R820T RTL-SDR and his homebrew QFH antenna. During his research he found that Brazillian Mexican Pirates hijack military satellite transponders to send SSTV pictures of their families on 255.560 MHz 22.4° West UFO F7 (USA 127).

Happysat writes that he found an active signal on that frequency most of the time. To receive the SSTV signal happysat used the free RX-SSTV software.

SSTV is an acronym for slow scan television and is a mode usually used on HF (0-30 MHz) frequencies by ham radio enthusiasts for sending out digital calling cards.

More information about pirate SSTV can be found here.

Edit: From our Facebook page comments, it seems these signals are actually from Mexican pirates. More info here http://www.qsl.net/py4zbz/ec/ec.htm.

Milsat Pirate SSTV
Milsat Pirate SSTV in SDR#
SSTV Image
Received SSTV Image 1
SSTV Image
Received SSTV Image 2

Tutorial: HF Decoding Tour with the FUNcube Dongle Pro+

On the FUNcube Dongle blog/store amateur radio enthusiast DK80K (a.k.a Nils) has sent in a link to a 16 page pdf file showing a comprehensive tour on the FUNcube Dongle Pro+’s capabilities on the HF spectrum.

He gives an overview of many digital ham and HF utility modes including DRM, WSPR, RTTY, Olivia, MFSK16, PSK31, Pactor, Packet, Hellschreiben, ROS, SSTV, HF ACARS, SSB, CW, DSC/GMDSS, SITOR-A/B, Globe Wireless, Time Signals, ALE, Baudot, FAX and Stanag 4285.

The FUNcube is a software defined radio similar to the RTL-SDR, but with better sensitivity and noise performance, but at a higher price (around $200 USD). These modes can also be received with the RTL-SDR and an upconverter such as the Nooelec Ham-It-Up upconverter.

Download his pdf here (Mirror)

Receiving SSTV with RTL-SDR

Over on the Radio Antics blog fellow RTL-SDR enthusiast Andrew has been using the RTL-SDR to receive Slow Scan Television (SSTV) amateur signals. SSTV is a method ham radio enthusiasts use to send small images to one another. The images often contain their ham call sign overlaid on the image.

Andrew was able to receive several SSTV images using an R820T dongle tuned to the 27 MHz (11 meter) band. He also used a Funcube Dongle+ and got similar results.

Check out his post for some of the images he received, and his video below for an example of the receiving process.