I would like to differ on that!!! its got nothing to do with the power supplies and the 'Synchronisation' of the supplies,The Strobe Lights flash twice the rate of the beacons( I dont remember the exact rate per second), but our brain is unable to synchronise the optical illusion of two kinds of lights flashing at such a high rate, whereas in reality both the lights flash at a constant rate (with beacons flashing half the rate of strobes) and hence the strobes appear to flash 'twice' together !!!
Its all in our BRAINS !!!!