BIRDS-2 CubeSats to Deploy from ISS on August 10

According to Masa Arai, JN1GKZ, Japan’s space agency JAXA has announced that three BIRDS-2 CubeSats with APRS digipeaters will deploy from the International Space Station on August 10. The trio — BHUTAN-1, MAYA-1, and UiTMSat-1 — will transmit 30 minutes after deployment. Initial mode should be CW on 70 centimeters; each satellite uses the same frequency of 437.375 MHz.

The normal transmission order is BHUTAN-1 (JG6YKL), MAYA-1 (JG6YKM), and UiTMSat-1 (JG6YKN). Each CubeSat also has an APRS digipeater on 145.825 MHz. Because the CubeSats will be released at the same time, it’s possible that the beacon signals from three CubeSats will interfere with each other as they will turn on at almost at the same time, making copy difficult.

Once on, one of the first things it does is transmit the beacon signal, but the CubeSats are programmed so that each will wait a certain amount of time before transmitting the beacon signal. The first satellite released will be the first to transmit, but it will remain silent for long enough to let other two satellites finish their beacon transmissions.

Source:ARRL