Pilot Ballon Observation Optical Theodolite

Pilot Ballon Observation Optical Theodolite :
For observing the quick ascending ballons in order to etermine upper wind velocities. Complete with all accessories in box and with stand.
General Design : The design and lay-out of the instrument is such that the Horizontal and vertical angles are read by means of two circles arranged in just a position horizontally. The vertical circle angles are transmitted by the use of accurace bevel gears, any backlash in this gearing being climinated be means of a spring device.
Optical System : This consists of main right-angled telescope with a pentagonal prism, magnification x 25 field of view 2.0" and a second "finder" or sighting telescope of shorter length, magnification x 6. field of view 8". This second telescope can be brought, into action by means of rotatable mirror in the horizontal barred, of the main telescope so that both telescopes are viewed by one eyepiece
which is screw focusing. The telescope is by means of a knurled ring behind the eyepiece. The diaphragm consists of a scale with divisions corresponding to 1/1000
Circles : Both circles are 5.25 in diameter, divided into half degree and reading on opposite sides bt common indices. Horizontal and vertical movement are earried out by means of worms and wom wheels. The worm spindles carry drums which sub-divide the circle readings to tenths of a degree. These drums are fitted with short handles to enable them to be revolved with rapidity A throw in and out mechanism is operated be levers on either side of the instruments for disengaging the horizontal and vertical worm spindles.
Sights : An open sights is provided for quick laying of Ballon immediately after it is released.
Tripod : The wooden tripod is provided for use of the Theodolite.
Accessories : Standard accessories packed in wooden box.
Technical Specification :-

Main Telescope
Magnification : 20 X
Field of view : 2 Deg.
Sightting Telescope
Magnification : 5 X
Field of view : 8 Deg.
Circle Graduation : 0.5 Deg.
Drum Reading : 0.1 Deg.
Weight of Instrument with case : 14 Kg.
Net Weight : 8Kg. (Approx.)
Tripod Weight : 4.5Kg. (Approx.)
Overall Size of case : 340 x 280 x 220mm
Tripod : 1.5 meter