Here is a versatile and reliable supply for experiments requiring medium to high voltages at relatively low currents, such as the Millikan Oil Drop experiment. The 50 and 500 VDC outputs are independently
variable, providing up to 50 mA, and the output displays can be switch-selected to read voltage and current in either range. A separate set of output terminals provides 2, 4, 5, 6 and 7 VAC at up to 3 A, a convenient source for electron tube filaments.
Note: The positive terminal of the 50 V supply is internally connected to the negative terminal of the 500 V supply.