All being well we are looking at releasing two balloons this weekend in Victoria.
Balloon No. 1 weight 80 grams UHF radio transmitters 434.650 FM 25 mw, Transmitting on FM mode BPSK 1000 and BPSK63F modulation. This will also be transmitting images with an on board camera.
Balloon No. 2 weight 220grams transmitting on HF 10.139.250Mhz and 10.139.250 Mhz 25mw JT65 and JT9 HF mode
UHF 434.650 Mhz Balloon Payload
After lots of development and testing our new FMPSB module has been performing fantastic!
FMPSB output level and deviation test
Our new FMPSB module is driven by a Teensy 3.1 ARM Processor using a Radiometrix NTX2 that transmits Thor 16 and FEC 1200, 4800, and 9600 FEC based on FX25, additionally the FMPSB can transmit APRS and SSDV.
One of the reason to develop a payload on FM is to enable anyone with a scanner receivers to be able to participate with the tracking without having to use a SSB receiver. I think we will also find some advantage in being able to quote a stationary frequency in order to detect the payload unlike the drifting we had with SSB. High altitude tests are still to take place to see how stable this frequency will be.
We are hoping to involve enthusiast with tracking that are not necessarily radio hams.
Top side of FMPSB with the 25mw Radiometrix module and power inverter under side.
GPS is a uBLOX MAX-7 Pico Breakout with Chip Scale Antenna
UHF Antenna is a 1/4 vertical. Payload is shown upside down
Payload
Payload with one Saft Li-SOCl2 Lithium Battery
QuadCopter Payload Test
QuadCopter Payload Test
Hovering at only 500 meters AGL our payload could be heard more than 70 klm away from Romsey Victoria over into the Melbourne South Eastern Suburbs. Not bad for 25mw FM