HI I'm trying to make a coolant temperature warning alarm just for a hobby.
I'm using an LM393 As a voltage comparator and an LM358 to pulse he buzzer on and off. I have made 2 separate circuits on a bread board to test, both circuits work perfectly. but now i cant get the two circuits to talk to each other. I want the buzzer to sound when the coolant temp sensor reaches a certain temp. Iv attached both diagrams I'm using. The potentiometer in the comparator circuit is being used to simulate the temp sensor. Any help or guidance appreciated.
Many thanks