Radio Astronomy and SDR Dongles

Measuring RF Noise Sources with a SDRDavid Morgan 2W0CXV has released several papers covering the use of the RTL-SDR Dongle in radio astronomy.

In 2011 David described the equipment configuration and software involved in setting to work a small 3m diameter amateur radio telescope using the FUNcube Dongle Pro software defined radio receiver.

At the end of 2014 he published a paper dealing with the setting up and use of a RTL-SDR dongle to receive meteor pings from the Graves Radar on 143.050 MHz.

He has now released two new papers covering the measurement of signal strength and  RF noise sources with the RTL-SDR.

Download David’s papers from http://www.dmradas.co.uk/Downloads.html

You can join the BAA Radio Astronomy Yahoo Group at
http://groups.yahoo.com/group/baa-rag

More ISS Slow Scan TV Activity

ISS SSTV image 9/12 received by Frank Heritage M0AEU at 19:21 UT on Dec 18, 2014

ISS SSTV image 4/12 received by Frank Heritage M0AEU at 19:21 UT on Dec 18, 2014

The Russian Federal Space Agency (Roscosmos) has announced another round of amateur radio Slow Scan Television (SSTV) activity from the International Space Station (ISS) will take place. Continuous operation, using the call sign RS0ISS, is expected during Sunday, February 22 and Monday, February 23.

ISS SSTV image 9/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR on Dec 18, 2014

ISS SSTV image 9/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR on Dec 18, 2014

Twelve different images will be sent on 145.800 MHz FM using the SSTV mode PD180, with a 3-minute off time between transmissions.

One of the photos shows the commemorative diploma created by PZK, the national Polish Amateur Radio society, on the occasion of the 80th anniversary of the birth of first cosmonaut Yuri Gagarin.

The equipment used will be the Kenwood D710 transceiver located in the Russian Service Module. It is thought the equipment may be producing about 25 watts output which should provide a very strong signal.

Plans are being discussed for transmitting new images from space enthusiasts around the world in the coming months. Additional details will be released.

The images received by amateurs world-wide during previous transmissions can be seen at http://www.spaceflightsoftware.com/ARISS_SSTV/ and you are invited to upload any pictures you receive during the upcoming transmissions.

In the UK newspaper the Daily Mail, Jonathan O’Callaghan wrote about how 22-year-old Radek Karwacki, an AMSAT-UK member, received pictures from the ISS using a £10 ($15) RTL-SDR dongle and a dipole antenna, see https://amsat-uk.org/2015/02/04/iss-sstv-in-uk-press/

International Space Station - Image Credit NASA

International Space Station – Image Credit NASA

All you need to do to receive SSTV pictures direct from the space station is to connect the audio output of a scanner or amateur radio transceiver via a simple interface to the soundcard on a Windows PC or an Apple iOS device, and tune in to 145.800 MHz FM. You can even receive pictures by holding an iPhone next to the radio loudspeaker.

On Windows PC’s the free application MMSSTV can be used to decode the signal, on Apple iOS devices you can use the SSTV app for compatible modes.

The ISS puts out a strong signal on 145.800 MHz FM and a 2m handheld with a 1/4 wave antenna will be enough to receive it. The FM transmission uses 5 kHz deviation which is standard in much of the world apart from the British Isles and Europe where 2.5 kHz deviation is more common.

Many FM rigs can be switched been wide and narrow deviation FM filters. For best results you should select the wider deviation filters. Handhelds all seem to have a single wide filter fitted as standard.

The ISS Fan Club website will show you when the space station is in range.

ISS SSTV image 12/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR Dec 18, 2014

ISS SSTV image 12/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR Dec 18, 2014

Paul Turner G4IJE, co-developer of the SSTV PD modes, says regarding the MMSSTV PD180 mode: “Don’t forget to either enable “Always show RX viewer” or use the “Picture viewer” (magnifying glass icon) to show the picture at its real resolution of 640 x 496. If you just view as normal you will only see 320 x 248 resolution, which kind of defeats the object of using a high resolution mode.”

On the AMSAT-BB Rick W2JAZ and Alan WA4SCA comment on the need to set the MMSSTV sound card setting to 48 kHz instead of the default 44.100 kHz
• Options
• Setup
• Misc
• Then the Clock section at the bottom of the page

The MMSSTV default setting may need to be set to 24000 (exactly half of the sound card setting). You then should get good clean images.

The sound card adjustments will vary slightly depending on the version of the OS you are running, but usually will be under the advanced properties for the device. You can probably use a higher sampling rate for the sound card so long as it is a power of 2 multiple (2,4,8, etc) of the value in MMSSTV. For instance 192k (8x) has no issues. The same applies to most similar software.

You can receive the SSTV transmissions online using the SUWS WebSDR remote receiver located near London along with the MMSSTV software https://amsat-uk.org/2014/08/15/suws-websdr-moves-to-new-site/

ISS Fan Club – Tracking / Predictions http://www.issfanclub.com/

Free MMSSTV Slow Scan TV software http://hamsoft.ca/pages/mmsstv.php

iOS SSTV App https://itunes.apple.com/gb/app/sstv/id387910013

For more on Slow Scan Television SSTV, see this article SSTV – The Basics
http://www.essexham.co.uk/sstv-the-basics

How to be successful with the ISS Slow Scan Television (SSTV) imaging system
http://www.marexmg.org/fileshtml/howtoisssstv.html

IZ8BLY Vox Recoder, enables you to record the signals from the ISS on 145.800 MHz while you’re away at work http://antoninoporcino.xoom.it/VoxRecorder/

ARISS Slow Scan TV (SSTV) Blog and Gallery http://ariss-sstv.blogspot.co.uk/

Information on the MAI-75 SSTV experiment
http://www.energia.ru/eng/iss/researches/education-26.html

Video showing reception of SSTV using the FUNcube Dongle Pro SDR and SDR-RADIO going into Virtual Audio Cable (VAC) then to MMSSTV software https://www.youtube.com/watch?v=K6MOrX9iZCk

ISS SSTV received online with SUWS WebSDR
https://amsat-uk.org/2014/09/06/iss-sstv-on-suws-websdr/

ISS SSTV 1/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR Dec 18, 2014

ISS SSTV 1/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR Dec 18, 2014

ISS ham radio SSTV in UK press

International Space Station - Image Credit NASA

International Space Station – Image Credit NASA

The Daily Mail reports that 22-year-old Radoslaw Karwacki received the recent amateur radio Slow Scan Television (SSTV) transmissions from the ISS

ISS SSTV image 9/12 received by Radek Karwacki on February 1, 2015

ISS SSTV image 9/12 received by Radek Karwacki on February 1, 2015

Radoslaw (Radek) used an RTL-SDR dongle costing about £10 ($15) to receive the SSTV signal on 145.800 MHz FM during the weekend of January 31 to February 1. The antenna was a simple dipole and he used the free SDRSharp and MMSSTV software to receive and display the image.

‘These images are not transmitted regularly. I was really lucky to receive them, because it was my first experience with this kind of equipment,’ he told MailOnline.

‘I blindly tuned in on that frequency during ISS flyby and happened to receive the signal.’

Read the article by Daily Mail Science and Technology reporter Jonathan O’Callaghan at
http://www.dailymail.co.uk/sciencetech/article-2939725/How-chat-astronauts-aboard-ISS-USB-dongle-antenna-lets-Polish-man-receive-images-cosmonauts.html

Radoslaw Karwacki’s original Reddit post and comments
http://www.reddit.com/r/RTLSDR/comments/2uibm1/i_received_these_images_from_the_iss_on_145800mhz/

ISS SSTV https://amsat-uk.org/2015/01/31/iss-sstv-operational/

How to receive ISS SSTV https://amsat-uk.org/2015/01/29/iss-sstv-this-weekend/

What is Amateur Radio ? http://www.essexham.co.uk/what-is-amateur-radio

Using the RTL-SDR dongle to detect meteors

Combined SDR# and Spectrum Lab Display - Dr David Morgan 2W0CXV

Combined SDR# and Spectrum Lab Display – Dr David Morgan 2W0CXV

A new paper has been released by Dr David Morgan 2W0CXV on using the RTL2841 DVB TV Dongle as a SDR processor with SpectrumLab.

The paper Techniques for using the RTL Dongle for Detecting Meteors covers the setting up and use of the dongle to receive meteor pings from the Graves Radar on 143.050 MHz.

It can be downloaded from the Meteor Detection Projects page of the BAA-RAG website http://www.britastro.org/radio/projects/meteorproj.html

Join the BAA-RAG Yahoo Group at http://groups.yahoo.com/group/baa-rag

Download the free publication RAGazine from http://www.britastro.org/radio/downloads.html

ISS SSTV reception on a portable setup using RTL-SDR

Standing in a car park, I was able to successfully receive the images using a handheld 3 element 144 MHz Yagi antenna connected to a RTL-SDR USB dongle.

The dongle was connected to Windows-8 tablet using a USB OTG cable.
I was running SDR# to listen and record the FM audio on 145.800 MHz.
I had a LNA connected between the antenna and rtl-sdr but since the the downlink from the ISS was quite strong it was probably not required.

M0JJS

Watch ISS SSTV reception on a portable setup using RTL-SDR

ISS SSTV https://amsat-uk.org/2014/12/18/iss-sstv-success/