| 摘要 |
Monitoring of a burner-generated flame in a flame zone is achieved by watching for changes in amplitude of radiation leaving the flame zone using an opto-electric transducer (34) and a processing circuit (50) which is tuned to a flicker frequency pass band targeted on the looked-for flame. A tunable band-pass switched capacitor filter (54) feeding into a threshold detector (62) via an AC/DC converter (61) is preferred. |
