Improvements in and relating to apparatus for detecting carbon monoxide

摘要: 835,933. Electric measuring systems. COAL INDUSTRY (PATENTS) Ltd. April 11; 1958 [April 11, 1957], No. 11881/57. Addition to 756,662. Class 40 (1). [Also in Group XL (c)] The apparatus for the determination of percentage carbon monoxide an atmosphere described parent Specification by temperature difference between two: thermistors each atmosphere, one being also located contact with oxidizer, teinperature determined change resistance, is modified using transistors instead thermionic valves electrical circuits, additional ambient compensation. As shown, a transistor oscillator T1 has large degree negative feed-back base and emitter, positive via transformer TT1 sufficient saturate on swing cut it off swing, produce rectangular output voltage zero maximum value emitter resistors R4, R5, R6 selected switch SW1a, adjusted potentiometer VR1. The. feeds through buffer stage T2 bridge incorporating 4, 5. unbalance amplified T3, T4, whose gain potentiometers VR2, VR3 differ from optimum sense compensate variation sensitivity temperature, rectified at MR, be shown meter M1, control audible alarm PH visual WL relay winding RL.