Equipment to collect meteorological data:
Data: wind direction, wind speed, temperature, Hygrometer to measure air humidity and dew point (additional option). Barometer to record air pressure. Works up to 9000m above local datum or 60 minutes flight duration.
Notes: Windsond is a miniature version of the radio sond devices that meteorological agencies around the world use to collect standard weather data. It includes small latex balloons, a small data logger with radio transmitter, and a laptop interface to receive radio transmissions from the data logger and present them in graph form. It also has powerful mapping software to display the location and altitude of the data logger for recovery. The sond can be adapted to sit in a larger payload with parachute for recovery. Data is not stored on the pcb and only the data received can be stored and interrogated.
Hexpert Zlog 7
Data: latitude, longitude, altitude, probe temperature, atmospheric pressure. 240 minutes recording time. No practical altitude limit.
Notes: Zlog 7 is a very simple gps and temperature data logger. Running on a 9v battery, it requires very little skill to use. As soon as the data logger is switched on, it starts to record position and temperature data, continuing until it is turned off.
Skyprobe
Data: latitude, longitude, altitude, atmospheric pressure, internal/external temperature sensor, solar Infrared levels, visible light, and humidity. 240 minutes recording time. No practical altitude limit.
Notes: Skyprobe is very similar to the Zlog 7 but records a much greater range of meteorological data. It also runs on a 9v battery.
GQ GMC-320-Plus Geiger Counter
Data: Gamma radiation in counts per minute. 240 minutes recording time.
KKmoon Mini Portable USB LCD Digital Temperature Humidity Data
Data: Temperature and humidity
Raspberry Pi met station
https://www.raspberryweather.com/
Data: temperature, and humidity
High Altitude Balloon resources
These give you an idea of how far balloons travel and how high they go.
http://habhub.org/calc/ Balloon burst calculator
http://predict.habhub.org/ Balloon flight path tool
Note: neither web sites cover balloon sizes below 200gm, however the 200gm forecast gives a clear indication of balloon trajectory for 30 and 100gm balloons.
Balloon Payload Recovery
Satellite Messengers: SPOT, inReach
Radiotracker: Pi in the sky, Habduino
Balloon News 