A simple and convenient way to interface 2 relays for switching application in your project. This relay driver boosts the input impedance with a regular BC547 NPN transistor (or equivalent). Very ...

Now, the water level begins to decrease and the shorter sensor will be no longer in contact with the water, but IC1C output will be hold high by the signal return to pin #5 of IC1B, so the pump will ...

Well-known industry author and instructor Jim Johnson is offering a new video for technicians who want to sharpen their troubleshooting skills. "This HVAC training video program, is available in DVD ...