Attached is a circuit to switch the polarity to a 12V solenoid. The problem is that it only gives me 7V instead of 12V and overheating some components. Would anyone be able to shed some light on the problem? Or suggest a better solution other than using relays? I have a solenoid where I need to change the magnetic field depending on a condition of the main circuit which is not shown here. The current to the solenoid is normally off untill a voltage is put on the "Left" or "Right" in which case the solenoid is energized with the selected polarity. Your help will be so much appreciated.