A small universal quadrupole mass spectrometer

Abstract A universal quadrupole mass spectrometer (type Q60U) has been constructed for general laboratory and industrial purposes. Its 10 cm long analyser rod system, 1–60 amu mass range and 4·10 −4 A mbar −1 sensitivity make it a good residual gas analyser. Due to its high mass resolution it can be used also as an analytical instrument. It works as a total pressure gauge, too, saving the cost of a vacuum gauge. The bias and gain controls and audio-frequency signal generator of its leak detection unit complete the quadrupole as a sensitive multi-test gas leak detector.