We understand precisely what [Dan] is going through. We likewise bought a affordable wireless doorbell as well as are plagued by the batteries running down. When that happens, the only method you understand is when people begin pounding on the door since you’re not answering the bell. Well no more for [Dan]. He developed a backup system which screens the voltage of the batteries on the chime unit.
You can see the little bit of protoboard he utilized to home the microcontroller as well as the UI. It’s an ATtiny13 together with a eco-friendly LED as well as a single push button. The concept is to utilize the chip’s ADC to screen the voltage level of the pair of batteries which power the chime. When it drops below 3V the eco-friendly LED will come on.
First off, we desire these things would include much better power supply circuits. For instance, we just replaced the CR2032 in an Apple TV remote as well as determined the voltage at 2.7V. That remote as well as the chime both run from a 3V source. Can’t they be made to work down to 1.8V? however we digress.
In addition to tracking voltage [Dan’s] rig likewise counts the number of times the chime has rung. Every eight seconds it flashes the count in binary, unless he presses the red button to remove the count. This is shown in the video after the break. We assumption he wishes to understand exactly how many times this thing can be utilized before running the batteries down.
Seriously though, for a seldom utilized product such as this exactly how difficult would it be to utilize ambient light harvesting to assist save the batteries? looking at some indoor solar harvesting numbers shows it may be impossible to only power this from PV, however what if there was a super-cap which would be topped off with a trickle from the panels however would still utilize the batteries when that runs down?