Help with a miss and voltage drop

A/C equals alternating current.
Your alternator produces alternating current; the same type of electricity that runs almost everything in your house.
But in order for your car to be safe, this alternating current has to be changed into DC,aka Direct Current. The device that does this is usually built in to the alternator, and is called a diode. There are usually 6 of them and they are very robust devices. But occasionally they fail, usually only one, or one atta time. And then A/C, or alternating current leaks into the DC system. Of course most of the wiring on your car is not designed to operate on AC, so chit happens. It just so happens that electronics are the most sensitive to this chit.
The lights don't care, unless the AC is too high or lasts too long. Same with the battery, or even the starter.
But not anything electronic, from the radio to the ignition Ecu, to the regulator.
So, when chit happens to me, I just put the DVOM on the alternator and look for an AC component.
And sometimes the lights flicker.......