I’m wondering if someone can help me. I’m building some filter circuits to run with my Milwaukee m18 batteries. I’m going to have one 9v and 2 18v outs. One of the 18v outs is going to run an amp. I’m using a linear voltage regulator L7809. To get the 9v. For some reason when I hook up my battery to the circuit the regulator is getting hot. I’m using this circuit. . Maybe someone has a better way to do this or can help?
Bearing in mind that i know next to nothing about power supplies... I think (not sure) that the LM7809 should be heatsinked... at least I've seen it this way on some PSU layouts and projects.
Hope this helps!