POWER SUPPLY FLASHING BEACON PRE 79 AA SERIES [ยง24]
This unit powers the flashing beacon on the tail by sourcing or draining current to light and dim the bulb on the vertical stabilizer. Used in conjunction with the ballast resistor, it provides a smoothly varying voltage to the beacon bulb, resulting in a nice fade-in, fade-out of the beacon.
Grummanologist:
Be sure and check that your ballast resistor, located forward of the ELT unit, is in good shape using a multi meter to measure the resistance across it. The ballast resistor sinks a considerable amount of current when dimming the beacon and can crack if exposed to excessive heat.