Question

If the positive lead of a DMM, with the mode set to ohmmeter is connected to the base and the negative lead to the emitter and a low resistance reading is obtained, then what is the type of transistor that is being tested?

(a) NPN

(b) PNP

(c) Faulty transistor

(d) Not a transistor, it is a FET

This question was posed to me in an interview for internship.

My doubt stems from Limits of Operation in portion BJT Biasing of Analog Circuits

Answer 1

Right option is (a) NPN

The explanation: There are multiple ways to test the BJT to be npn or pnp using a DMM based upon which terminals are connected to which lead of the DMM. If positive is to base and negative to the emitter of the BJT, and if a low reading is obtained and not a over limit, then the transistor is NPN.