Martin Brenner's, Pilot Balloon Resources 

Helium or hydrogen compressed gas tank with regulator and hand operated valve (valve may be present in nozzle assembly). Note:  hydrogen is volatile, this document does not provide instruction for its safe use and handling. It is highly recommended that only Helium is used unless all persons have been adequately trained in safe practices with hydrogen. Additionally Hydrogen requires specialized equipment and procedures to insure that all sources of ignition are 100 percent suppressed. Helium is totally non reactive and while not as light as hydrogen (less free lift) it is not a combustion hazard.

Balloons, fillers and weights
Some examples of fillers and weights are illustrated on this web site.  10, 20, 30 and 100 gram weather balloons are used.  30 and 100 gram balloons are used most often.   Balloon suppliers can be found on pages on this site.   Larger balloons 100 gram, use large quantities of helium and are costly. They are primarily used for soundings where readings at high altitudes are required, night time ascents where the balloon needs to carry a lighting device, or where high wind conditions require high ascent rates.

Fillers are hollow brass or light alloy nozzles shaped to accommodate balloon necks of the diameters to be used, in some cased they contain a unidirectional gas valve. Weights can be added to the filler so that the combined weight of the filler and the weights equals the desired free lift for the balloon tyep being inflated.

Theodolite and accessories
A Pilot Balloon Theodolite that is properly adjusted, a sturdy tripod or fixed mount, cover for theodolite and appropriate lens shades and filters when necessary.

A stop watch (or pibal timer) clipboard with paper and pen, an assistant to transcribe readings.

Lighting units, a flashlight, and batteries for night work. Many theodolites have an integrated lighting system to illuminate the scales, micrometer drums and crosshairs for night time work.

A prismatic compass (if the theodolite does not have an integrated compass) and the magnetic declination for the location of the observation point. (the declination will allow you to set the theodolite orientation to true north where true north base wind readings are required).

A computer and suitable program for reducing the observation data to wind data. An  excel spreadsheet will be available soon on this web site. Other programs are available commercially.