This voltage monitor circuit is designed using LM393 operational amplifier and it has two has two light-emitting diode (LED) indicators that switch on if the monitored supply voltage falls below separate threshold levels.
This voltage monitor circuit can be used to monitor the DC supply voltage, and it will then give a warning if the supply voltage drops to an inadequate level due to a malfunction.
With the specified components values the circuit provides threshold potentials of 10V and 12V.
This fishing warning circuit electronic project is very simple and can be used as an indicator useful in fishing. The fishing warning circuit signals when a fish took the bait. When you hooked a fish, sensor close current terminals situation where both LEDs light. In addition to this diode, a buzzer can be used to generate an acoustic signal. D2 continues to shine even after reopening sensor until SCR no longer receives holding current. In this way, any hook thread tension is indicated by D1.