Ref: Silicon Chip July 2016

Monitor the operating temperature of your fish tank, fridge/freezer, hot water system, incubator or anything else that needs a stable thermal environment. It will monitor temperatures in the range of -33° to 100° Celsius and provide an audible alarm if the temperature goes outside a pre-set range as well as switch on one of two LEDs - red for too hot, blue for too cold. The upper and lower temperature thresholds are adjusted via two trimpots and a calibration chart is included in the instructions. The circuit itself is easy to construct with no surface mount devices and is housed in a standard UB5 jiffy box.

Power: 9-12VDC
PCB Dimension: 78(L) x 47.6(W)mm