Hi there, I bulit a kind of Multiwire Proportional Chamber in my Institute to detect cosmic muons on sea level. The chamber consists of Plexiglas and contains a double capacitor. The cathodes are two copper plates and in-between the plates the anode which is a grid of wires. The distance between the anode to one of the cathode plates is 10mm, the distance between the wires is 2mm. I worked with a silver coated copper wire with a diameter of 0.1mm. The chamber is airthigt, and filled with a gas mixture of 90% Ar and 10% CO2, the pressure is 1 bar (100000 Pa). I calculated the whole event, with the Energy transformation of the muons to Ionisation of the gas (Bethe-Bloch-Equation), the number electron/ion pairs produced, the amplification in the proportional range. I calculated a voltage puls, that I should measure, of more then 10 V with an impressed voltage of 2.5 kV. The Problem: I impressed a voltage up to 2.5 kV with no result of any voltage puls. What should I do now? Should I raise the voltage until there is a discharge? Should I change the distance between anode and kathode? or what else? Thank you for your help.