A realtime power mask trigger generator for an instrument that acquires data in response to a trigger signal integrates power amplitudes over a defined bandwidth within a frequency spectrum for an input signal to produce an average signal power, and compares the average signal power with a specified reference power level for the defined bandwidth. An inlet 29 is formed in the lower part of the inlet portion, and an outlet is formed in the side face of the outlet portion. Once the self-test is complete, the detector’s alarm is silenced and a remote self-test signal is sent to the interconnected remote hazardous condition detectors. In other variants of the invention the shoe weights may also be covered with a smooth rubber plastic. Reducing unnecessary power consumption is possible because the temperature of the fuser is controlled by differentiating a temperature ascending stage and a temperature descending stage from each other, and the quality of image may be enhanced and a flicker phenomenon is prevented. The memory generates the burst column addresses by modifying the least significant column address signals only.