Tag Archives: Ham Radio

Feb 24 2015

ISS SSTV in a Brazilian School

Paulo PV8DX of AMSAT-BR turned the recent Slow Scan TV transmissions from the International Space Station (ISS) into an education outreach opportunity for amateur radio.

On Monday, February 23, 2015 at the Gonçalves Dias school he explained amateur radio to the students and demonstrated receiving an ISS SSTV picture on 145.800 MHz FM.

The ISS pass he received did not produce a strong signal and only part of the picture was captured but as can be seen from the video the students were enthusiastic and excited to be receiving a signal from space.

Paulo expressed the hope that the ISS will send images on school days more often.

Watch ISS – SSTV , By PV8DX

AMSAT-BR https://sites.google.com/site/amsatbr/

Information on receiving ISS SSTV https://amsat-uk.org/2015/02/11/more-iss-slow-scan-tv/

Feb 24 2015

Space Station SSTV and Packet Radio via SUWS WebSDR

ISS SSTV and Packet Radio signals on the SUWS WebSDR

ISS SSTV and Packet Radio signals on the SUWS WebSDR

Martin Ehrenfried G8JNJ reports excellent SSTV and Packet Radio signals from the International Space Station (ISS) using the online SUWS WebSDR.

144 MHz prototype helix antenna

144 MHz prototype helix antenna

The omni-direction helix antennas at the WebSDR were designed with high elevation satellites in mind. Conventional antennas concentrate the radiation pattern towards the horizon resulting in weaker signals when a satellite is above 15 degrees elevation. Comparisons with other WebSDRs show the SUWS antennas provide a 6 to 10dB better signal to noise ratio on similar passes.

Martin says: “I had been experimenting with single turn ‘twisted halo’ design, and decided to try stacking them to see if I could achieve more gain. Modelling suggested that a stretched 3 turn helix with a helix circumference of approx 1/2 wave length and an overall length of 1/2 wave at 70cm, and fed with a gamma match at the centre would offer reasonable gain, an omni-directional pattern and mixed polarisation.”

You can use the free online SUWS Web Software Defined Radio from your PC or Laptop to receive the ISS and the many amateur radio satellites transmitting in the 144-146 MHz or 435-438 MHz bands. It also provides reception of High Altitude Balloons in the 434 MHz band and coverage of the microwave 10368-10370 MHz band.

The SUWS WebSDR is located at Farnham not far from London, 51.3 N 1.15 W, listen to it at http://websdr.suws.org.uk/

Full details of the antennas are available at http://g8jnj.webs.com/currentprojects.htm

Brazilian radio amateur uses SUWS WebSDR to receive ISS SSTV
https://amsat-uk.org/2014/09/06/iss-sstv-on-suws-websdr/

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

Feb 22 2015

IARU-R1 VHF Newsletter Released

IARU_Region_1_logoIARU Region 1 has released issue 65 of the VHF-UHF-uW newsletter, it covers WRC-15 which could affect a number of amateur radio bands.

The newsletter says agenda items at the ITU World Radiocommunication Conference includes topics that affect amateurs in the 5MHz, 5GHz, 10GHz, 24GHz and 77GHz bands.

WRC-15 decides the agenda items for the next conference (WRC-19). IARU Region 1 has proposals in CEPT concerning these potential agenda items:
• 50 MHz Amateur-Satellite Service allocation
• 3.4 GHz harmonisation

There may be a need to raise the option of a new allocation such as 1300-1310 MHz in order to mitigate restrictions that are appearing in the existing 23cm band.

Read the newsletter here

Feb 22 2015

Stunning Results from ISS SSTV

ISS SSTV image 2 received by Andrew Garratt M0NRD Feb 22, 2015

ISS SSTV image 2 received by Andrew Garratt M0NRD February 22, 2015

The ISS Slow Scan television Transmissions have already produced some great pictures, more will be sent Monday, February 23 on 145.800 MHz FM until 2130 UT.

On the AMSAT Bulletin Board (AMSAT-BB) Clint Bradford K6LCS posted:

Receiving SSTV from the ISS really CAN be simple: For my first time ever, I simply fired up a $3 iOS app, and held my iPod touch near my Yaesu FT-60R’s speaker, and downloaded one of the images from the ISS.

I didn’t think there was too much left in the hobby to excite me – but I was WRONG!!!

Greg KO6TH said “I’ve never received a clearer SSTV picture from anywhere, let alone outer space!”

Twelve different images depicting space pioneer Yuri Gagarin – the first human to orbit Earth – are being sent on 145.800 MHz using the SSTV mode PD180, with a 3-minute off time between transmissions.

The transmitter on the ISS uses 5 kHz deviation FM. If your rig has selectable FM filters (most mobiles do) make sure you choose the wider setting designed for 20 or 25 kHz channel spacing, usually marked FM or FMW.

Images received so far by radio amateurs world-wide are at
http://www.spaceflightsoftware.com/ARISS_SSTV/

Find out more about receiving these transmissions and links to decoding software at
https://amsat-uk.org/2015/02/11/more-iss-slow-scan-tv/

Feb 22 2015

Amateur Satellite Tutorial Videos

David Casler KE0OG has released a series of tutorial videos for the US Extra class license two of which cover amateur radio satellites.

The first deals with Orbital Mechanics and the second covers the radio aspects of amateur satellites.

Watch Extra Lesson 2.3, Amateur Satellites (Part 1)

Watch Extra Class Section 2.3 Satellite Operations (Part 2)

See the other tutorial videos at https://www.youtube.com/user/davecasler/videos

Feb 19 2015

SatNOGS give prize money to LSF

SatNOGS - Satellite Networked Open Ground Station

SatNOGS – Satellite Networked Open Ground Station

SatNOGS won the Hackaday grand prize of $196,418 for their satellite ground station, they plan to give the money to the Libre Space Foundation.

The Libre Space Foundation (LSF) is a non-profit foundation registered in Greece by the creators of the SatNOGS project. The aim of the foundation is to promote free and open source technology in space and support, develop and fund space projects.

Ground Stations are Just the Beginning: The SatNOGS Story
http://hackaday.com/2015/02/19/ground-stations-are-just-the-beginning-the-satnogs-story/

SatNOGS Win Hackaday Prize https://amsat-uk.org/2014/11/14/satnogs-win-hackaday-prize/

SatNOGS – Satellite Networked Open Ground Station https://satnogs.org/

Libre Space Foundation http://librespacefoundation.org/