Sensitive Freezer Alarm with Buzzer

Here is a simple freezer alarm circuit, but ultra sensitive with a buzzer. The circuit raises an audio alert when the temperature inside the freezer box

FlashCheck® Certified Min/Max Alarm Thermometer, Model 12238

PHCbi PF Series Undercounter Laboratory Medical Freezer (-20°C

Make this Simple Refrigerator Door Open Alarm Circuit - Homemade

Simple Refrigerator/fridge Door Alarm circuit

refrigerator door alarm - #21 by hein3144 - Project Guidance

Simple Touch Alarm circuit

Fridge-tag® Ultra Low Data Logger - Thermco Products

Temperature Alarm Circuit using BC547 Transistor

Handy Pen Torch Circuit

80°C Ultra Low Temp Under Bench Freezer