Need a simple alarm (buzzer) that is triggered when the voltage drops.

AnalogKid said:

As wonderful as the 4060 is, it does have a relatively low-precision oscillator section. Now that you have a reference point defined by R9, C1, and the 8.5 minute delay period, you can decrease either the R or the C to speed up the oscillator and shorten the delay. Changes should be directly proportional, so if you change R9 to 62K, the delay should shorten to 5.27 minutes (-ish). 59.0K 1% tolerance should get you very close to 5.0 minutes.

ak

Click to expand...