'73 240z ignition switch bad; keep hearing a relay kick on and off

[Yellow240z73]

so the other night i had pulled in the driveway and shut the car off, but due to a bad ignition switch, she started back up when i rotated the key around to "lock". so i yanked the coil wire, but didn't pay much attention to the relay i keep hearing kick on and off every 10 seconds or so in the lower passenger side of the dash. what is going on here? it killed my battery. i believe it also did the same thing when i tried the new ignition switch (couldn't install it yet), but my new ignition switch was in the off position. also i believe it is making my alternator turn off and on while driving (the car will be sluggish like it's being starved of electricity). could this be a voltage regulator? or another electrical component that has gone bad? it's driving me insane cuz i can't drive it much since i have to disconnect the battery where ever i go.