Franck-Hertz apparatus Franck-Hertz apparatusArt No.20801.01To prove Bohr's theroy of atomic energy level.It takes a tube filled with argon as a F-H tube.Voltage supplied to F-H tube:UG1K 1.3-5.0V,UG2K 1.3-1.5V,UG3K 0-100V UN 3V,3.5V,4V,5V,5.5V,6.3VNo. of spectrum amplitude by point-measuring:=5No. of spectrum amplitude on osclliscope:=3