A balloon experiment by Warsaw University of Technology is planned to lift off on September 12, carrying a unique very-low-frequency (VLF) 210-meter long fully-airborne antenna system, and a transmitter on 14.2 kHz — the former frequency of the Babice transatlantic radio station in Poland. The project is to gather data for a doctoral dissertation, and any and all feedback on the reception of the signal is important.
The balloon will lift off in the early afternoon from Przasnysz Airport. The flight is set to last about 3 hours, with the balloon reaching a maximum altitude of 30 kilometers above sea level. The emission will be A1 (narrow-band carrier). Operation will start on the ground, with the antenna unfolding as the balloon ascends. Additional radionavigation signals: 144.8 MHz APRS (call sign SP5AXL). The VLF antenna center-fed half-folded vertical dipole with both capacitive and inductive loading.
via American Radio Relay League | Ham Radio Association and Resources http://www.arrl.org/news/view/university-in-poland-will-launch-balloon-with-vlf-transmitter-on-board