Digital Encyclopedia: Product Demo & Review

  ***  Relevant Material :  “True Alarm  photoelectric sensors use a stable, pulsed LED light source and a silicon photodiode receiver to deliver low power smoke sensing. There are three user-selectable sensitivities for special applications for each individual sensor: 0.2%, 0.5%, and 1% for each foot. Standard sensitivity is 1.25% to 3.1% for each foot. The fire alarm control unit can vary the sensitivity for normal applications between 1.25% and 3.1% for each foot. Note: Fixed sensitivity settings higher than 1.0% for each foot are not UL268 7th Edition compliant. The sensor head design provides 360° smoke entry for response to smoke from any direction. Due to its photoelectric operation, air velocity is not normally a factor, except for impact on area smoke flow... ‘’  ( TrueAlarm Analog Sensors – Photoelectric and Heat, Standard Bases and Accessories ) ***  Relevant Material:  Cleaning dust from a Simplex 4098-9714 photoelectric smoke detector (oft...

  *** Relevant Material: “  As of late 2024–2025, while mobile connectivity has expanded significantly, a substantial portion of the global population still lacks access to mobile internet or cellular services, with the gaps being primarily in  developing countries .   ITU  +1 Key Global Statistics on Disconnected Populations In 2024, an estimated 2.6 billion people (32% globally) were offline. A mobile coverage gap affects around  350 million people  (4% globally) who live in areas without mobile internet networks. Additionally,  3.1 billion people  (39% globally) reside in areas with coverage but do not use it. Combined, this means 43% of the world's population (3.45 billion people) does not use mobile internet. Sub-Saharan Africa is the least connected region, with only 27% of the population using mobile internet.   ITU  +3 Key Regional Statistics (Disconnected Populations, 2025) Significant numbers of disconnected people are fou...