The Philippines’ Satellite Ham Radio Service Is Now Live
Phillip Keane posted on May 20, 2019 |

Amateur radio users from across the ocean will now be able to communicate with amateur radio enthusiasts in the Philippines, thanks to the recent inauguration of the country’s first amateur radio satellite service.

The project has been developed under the STAMINA4Space program, a research program funded by the country’s Department of Science and Technology (DOST), which focuses on building local capabilities in satellite development, operations and education.

Figure 1.Locally developed AMU payload. (Image courtesy of STAMINA4Space.)
Figure 1.Locally developed AMU payload. (Image courtesy of STAMINA4Space.)

Generally speaking, amateur (ham) radio transmissions are limited in range by the horizon. The curvature of the Earth blocks a signal from propagating beyond the horizon. In principle, with a tall antenna and enough power, ham radio users can communicate up to a few hundred miles.

But in the case of satellite-based amateur radio systems, this issue is resolved by bouncing the radio signal off a satellite in orbit, and therefore sending the signal far over the horizon. How far exactly? Very far.

During the media event, operators at the University of Philippines Diliman were able to demonstrate communications with other ham radio users as far away as Japan by bouncing the signal of the Philippines’ Diwata-2 satellite in orbit.

Figure 2.Local ham radio enthusiasts and the STAMINA4Space team at the launch event. (Image courtesy of STAMINA4Space.)
Figure 2.Local ham radio enthusiasts and the STAMINA4Space team at the launch event. (Image courtesy of STAMINA4Space.)

Diwata-2 is a 56kg Earth observation microsatellite developed by the University of Philippines Diliman and DOST in collaboration with Tohoku University and Hokkaido University in Japan. It was launched in October 2018 from Japan, into a sun-synchronous orbit. On board the satellite were a number of different payload components, including the locally designed and manufactured Amateur Radio Unit (ARU).

In general, the ARU will extend the range of communications along the length and breadth of the Philippines, and is intended to assist with disaster relief operations in the event that other communications channels become overwhelmed or otherwise impaired. But, as we mentioned, anyone abroad who is underneath the path of the satellite as it orbits overhead will, in principle, be able to communicate with other radio operators who are also within the path of the satellite at the same time.

The ARU consists of the following features:

  • FM voice repeating (uplink/downlink)
  • APRS message repeating (uplink/downlink)
  • Morse-based beacon (downlink)
  • APRS-based beacon (downlink)

Because of the ARU, Diwata-2 is now designated by AMSAT as Philippines-OSCAR 101 (PO-101) and has the call sign DW4TA-1, which it uses when transmitting its automated signals.

OSCAR stands for Orbiting Satellite Carrying Amateur Radio and is the designation used by AMSAT, the amateur radio satellite body that monitors and documents satellite-based ham radio activities.

You can read more about how to connect to the Diwata-2 amateur radio service over at the project blog, at this link right here. But don’t forget, you’ll need a ham radio license if you wish to transmit anything.

And naturally, you will want to know when Diwata-2 is passing overhead if you wish to make use of the service. You can track Diwata-2’s overhead passes over at this link, or you can see regularly updated schedules over at the Diwata-2 Twitter page.

Figure 3. Handwritten messages from engineers on the ARU. (Image courtesy of Lorenzo Sabug, Jr., STAMINA4Space and UP EEEI.)
Figure 3. Handwritten messages from engineers on the ARU. (Image courtesy of Lorenzo Sabug, Jr., STAMINA4Space and UP EEEI.)

Recommended For You