Difference between revisions of "HAMTV from the ISS"
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== How can I build my own ground station to receive HAMTV? == | == How can I build my own ground station to receive HAMTV? == | ||
| − | Receiving HAMTV from the ISS is challenging. The link budget is a lot less forgiving of non-optimal stations than VHF/UHF, the 'microwave' frequency brings lots of pitfalls, the equipment can be expensive and/or hard to source, and the limited visibility and fast movement of the space station across the sky can make it time-consuming and frustrating to troubleshoot any problems that occur. | + | Receiving HAMTV from the ISS is challenging. |
| + | The link budget is a lot less forgiving of non-optimal stations than VHF/UHF, the 'microwave' frequency brings lots of pitfalls, the equipment can be expensive and/or hard to source, and the limited visibility and fast movement of the space station across the sky can make it time-consuming and frustrating to troubleshoot any problems that occur. | ||
The result however is being able to receive live video from an Astronaut (during school contacts), with your own S-band antenna. You could also talk to ARISS Ops about joining the ground station network and using your antenna to contribute directly to School Contacts. | The result however is being able to receive live video from an Astronaut (during school contacts), with your own S-band antenna. You could also talk to ARISS Ops about joining the ground station network and using your antenna to contribute directly to School Contacts. | ||
Revision as of 23:54, 29 August 2025
HAMTV is the name of the Digital Amateur Television (DATV) transmitter on board the Columbus module of the International Space Station (ISS). It is a DVB-S digital audio and video transmitter, normally on 2395MHz (13cm band).
The HamTV unit was first installed on the ISS in 2013, commissioned in April 2014 and was used for a number of ARISS school contacts in 2016 - 2018. The unit failed in 2019, and was brought back to earth for repair. It was returned to the ISS on the SpaceX SpX-30 flight on March 21st 2024. It was finally installed and first powered on again on 29th July 2025.
Current Status: HAMTV is off, waiting formal commissioning of the Test Card generator to replace the blank screen previously transmitted when no camera is plugged in.
Purpose
The primary use is for ARISS schools contacts, when the astronaut will use a camera to show live video of himself and the inside of the ISS to the school during the VHF radio contact.
Outside of school contacts the transmitter is often left switched on to enable experimentation and self-education in the building of ground stations.
Transmission Details
Whilst the transmitter has a number of possible configurations, it is anticipated that most transmissions will be:
- RF: 2395 MHz, RHCP, 2W power at the patch antenna pointing down from the ISS.
- Modulation: 2.0 Msymbols/second, DVB-S (QPSK), FEC 1/2
- Content: MPEG-2 video with MP2 audio.
More details can be found at: HAMTV from the ISS - HAMTV Transmitter Information
How can I watch HAMTV? (without a ground station)
A network of ARISS ground stations contribute to a central feed to enable high-quality reception for School Contacts, when stations are active you can watch this here: https://live.ariss.org/hamtv/
How can I build my own ground station to receive HAMTV?
Receiving HAMTV from the ISS is challenging. The link budget is a lot less forgiving of non-optimal stations than VHF/UHF, the 'microwave' frequency brings lots of pitfalls, the equipment can be expensive and/or hard to source, and the limited visibility and fast movement of the space station across the sky can make it time-consuming and frustrating to troubleshoot any problems that occur.
The result however is being able to receive live video from an Astronaut (during school contacts), with your own S-band antenna. You could also talk to ARISS Ops about joining the ground station network and using your antenna to contribute directly to School Contacts.
- Antenna - Typically a dish of 0.6-1.2 meters in diameter, needs some mechanism to point and follow the space station across the sky.
- Feed - Typically a helix or patch.
- LNA - Required, and mounted as close as possible to minimise coax loss at microwave frequencies.
- Filter - May be required to prevent overload if you have strong WiFi (2400MHz+) or 5G (2380MHz-) nearby.
- Downconverter - Optional, allows use of non-microwave capable receivers, also reduces loss in long coax runs.
- Receiver - Needs to be capable of receiving 2.4MHz-wide DVB-S. A good receiver can be more tolerant of issues elsewhere in the ground station.
For more information read: HAMTV from the ISS - How to build a ground station
Social media
Follow ARISS international on twitter for the latest status updates
https://twitter.com/ARISS_Intl
BATC forum
BATC have setup a new forum thread to discuss receiving HamTV.
Please post any questions, comments and status updates here: https://forum.batc.org.uk/viewtopic.php?f=2&t=8398
A lot of information is available on the BATC forum:
https://forum.batc.org.uk/viewtopic.php?t=4389
Youtube videos
Colin G4KLB made a video on how he received HamTV in 2014
https://www.youtube.com/watch?v=9keVA21DPBc
Video of HamTV in action during the Tim Peake Principia mission contact with Norwich schools in 2016.
https://youtu.be/DnJmxNCX4V4?si=RySuD0ft1Bcl1nTN
G8GTZ presentation on receiving HAMTV at the AMSAT UK conference in October 2023
https://www.youtube.com/watch?v=4J_JA3Syv6Y
Next generation HamTV presentation by Phil M0DNY at the AMSAT UK conference in October 2023
https://www.youtube.com/watch?v=MQvRdG1FBo4
Comments on this wiki page
If you have any comments on this wiki page or if you think we should add more information to it, please email them to wiki @ batc.tv