Depending on what kind of ignition you have hei or points. yes you should have voltage on both sides of the coil with the key on ... unless you have points and your points are closed. The easiest way to check it is with a test light turn the key on see if it lights up on both pos. and neg. if it does keep the light on the neg. side and have someone crank the engine it should pulse, if it does your coil is bad if it does not pulse your pick up/ or module / or points are bad.. hope this helps

simon