Radios, Modes and Antennas on the ISS
The ISS amateur radios are Ericsson MP-X handheld radios, a Kenwood TM D700 and a Kenwood D710.
Two hand-held Ericsson (M-PA Series) transceivers are on board in the ISS Columbus module: a VHF radio that receives and transmits FM voice or packet radio signals in the 2-meter (144 to 146 MHz) Amateur Band, and a UHF radio that receives and transmits FM voice or packet radio signals in the 70 centimeter (435-438 MHz) Amateur Band. Both radios are Ericsson (M-PA) series commercial grade radios. These radios look identical in size and features, but are specially tuned to support the different bands. Up to 5 Watts of output power is available on any one of 64 possible channels.
The Kenwood TM-D700 radio. located in the ISS FGB Service Module (Zarya), supports 2 meter (144-146 MHz) and 70 cm (435-438 MHz) operation. This radio provides a higher output power capability (restricted to a maximum of 25 Watts in ISS operation) supporting FM and packet operations. The higher power capability allows nearly horizon-to-horizon signal reception using simple hand-held radios or scanners. A set of 5 default options, or Programmable Memories, are embedded in the D700 to support ISS operations.
There are numerous channels programmed in the radios. Two of these channels on the 2 meter radio band support voice operations (145.80 down/144.49 up for ITU Regions 2 &3 & 145.80 down/145.20 up for ITU Region 1). It is necessary to use two uplinks due to region-to-region ITU restrictions on uplink frequencies.
The crew switches between one frequency to the other; scanning is not used. For example, if a crew member begins a QSO over the US, they can track US stations until they hit the Atlantic and then they will quickly lose US stations. They can then switch over to the other frequency and pick up stations in Europe or Africa.
Packet Operations
There is one radio on the ISS that operates as a packet digipeater. The Ericsson HT is about 5W and uses RS0ISS. It will respond to the alias "ARISS". With the Ericsson, you'll have better luck using more power and, if you have it, FM Narrow mode.
For information about using the ISS packet system, check out this resource provided by JoAnne Maenpaa, K9JKM.
SSTV Operations
Slow Scan Television (SSTV) images can be transmitted from the International Space Station. An SSTV system is an integral part of one of the ARISS ham radio stations, NA1SS/ RS0ISS in the Service Module. It transmits and receives JPEG still images.This system utilizes the Kenwood D700 and D710 radios and the ARISS antennas mounted on the Service Module. The SSTV equipment also includes SpaceCam and MMSSTV software, a radio/computer interface module and data cables. A Kenwood VC-H1 is also used to provide near real-time automatically transmitted images (usually earth views) once every 3 minutes, when active.
A Kenwood D710 radio located in the Service Module was deployed by the Russian Space Agency, Energia to provide extended support of imaging experiments using various SSTV formats. It employs SpaceCam and MMSSTV software to transmit stored images.
In preparation for future ISS SSTV events, a video demonstration of receiving SSTV from the ISS was created by avid ARISS supporter, John Brier, KG4AKV. In addition, John has provided an excellent online tutorial explaining in more detail how to configure a simple system to acquire and view the SSTV images. Links to both can be found at https://www.youtube.com/watch?v=7to9uX1sWC4 and https://spacecomms.wordpress.com/iss-sstv-reception-hints/.
To view, or submit, SSTV received images transmitted from the ISS and to follow SSTV operations, check out the ISS SSTV blog site.
HamTV System
HamVideo page. Currently under repair.
Antennas
A set of four antenna systems are deployed in the ISS Service Module supporting the current installation of the Kenwood D700 and D710 radios. Each of the four antennas can support amateur radio operations on multiple frequencies and allow for simultaneous automatic and crew-tended operations. Having four antennas also ensures that ham radio operations can continue aboard the station should one or more of the antennas fail. Three of the four antennas are identical and each can support both transmit and receive operations on 2 meter, 70 cm, L band and S band. They also support reception for the station's Russian Glisser TV system, which is used during spacewalks. The fourth antenna has a 2.5-meter (8 foot) long vertical whip that can be used to support High Frequency (HF) operations, particularly on 10 meters. Currently, one of the 3 VHF/UHF antennas is disconnected and the HF antenna has no radio hardware available for use.
Two antennas are installed in the Columbus module, currently serving the Ericcson radios deployed there. Frequencies available for transmission to and from Columbus are 2 meters, 70 centimeters, L-band and S-band. These antennas will also support the Ham TV DATV transmitter.