  A tracking detector system has been constructed with an innovative approach
to the classical multi-wire proportional chamber concept, using contemporary
technologies. The detectors, covering an area of 0.58 square meters each, are
optimized for the application of muon radiography. The main features are high
(>99.5%) and uniform detection efficiency, 9 mm FWHM position resolution,
filling gas consumption below 2 liters per hour for the non toxic, non
flammable argon and carbon dioxide mixture. These parameters, along with the
simplicity of the construction and the tolerance for mechanical effects, make
the detectors to be a viable option for a large area muography observation
system.
