Скачать или смотреть Pico Balloon Mission ZS1ERZ-12

Eden Radio Club in collaboration with Stewart ZR1WT, launched a pico-balloon, Mission ZS1ERZ-12, from the Ystervark Point Lighthouse in the Western Cape of South Africa on 16th August 2025 at 11:25am

The payload is a WSPR beacon which is constructed using a Raspberry Pico-Pi as the processor with an add-on board from Traquito that provides:-
GPS (ATGM336H)
Radio Transmitter (SI5351A) + 0.5ppm TCXO
Voltage Monitor

It is powered by 6 tiny solar panels each producing 0.5 volts at 400mA, with a total of 3 volts. However in full sunlight this can be greater than 4V. This is the only means of power - there is no battery on board - hence the payload only transmits during daylight when the sun is shining. Further, the angle of the sun needs to greater than 20 degrees in order for it to be strong enough.

I have chosen the 10m band (dial frequency is 28.1246 MHz) to transmit on. The transmission power is a mere 20mW (milli-watts).

Two WSPR transmissions are sent every ten minutes, beginning on the 2nd minute of each cycle (eg, 11:02, 11:12, 11:22, 11:32, etc). A supplementary WSPR transmission follows immediately after the first, (eg, 11:04, 11:14, 11:24, etc).

The onboard processor (a Pico-Pi) calculates the current six-character Maidenhead grid square. The first four characters are transmitted in the standard WSPR message, while the final two characters are conveyed in the second, non-standard message.

In addition to the extended grid information, the second WSPR message also reports temperature, altitude, ground speed, solar panel voltage, and GPS lock status.

Eden Radio Club team members:
Stewart ZR1WT
Corne ZS1COR
Willie ZS2CC
Eben ZS1HEB
Llewellyn ZS1VIS
Skollie RAE candidate for October 2025