... screen, and other performance parameters for testing LED tester:test electrical parameters such as PN junction of the forward voltage drop ... , reverse breakdown voltage, reverse leakage current,check whether short-circuit or break-circuit, Brightness uniformityTest targets:General of the nixietube,16 * 16 ... displayVf 0~19.99VIr: 0~99uA(PCB,PCBA,LED) LED electrical parameters tester(PCB,PCBA,LED)