🔍 Key Concepts

• Semiconductor diode behavior (like a crystal detector) • How an ohmmeter applies a small DC voltage and measures current/resistance • The idea of forward vs reverse bias for a rectifying device

💭 Think About

• If a silicon crystal in a RADAR mixer stage acts like a rectifier, how would you expect current to flow when you reverse the ohmmeter leads? • What would a completely open (burned out) crystal look like on an ohmmeter in both directions? What would a completely shorted crystal look like? • Which choice best matches the expected behavior of a good semiconductor junction when tested with a simple DC ohmmeter?

✅ Before You Answer

• Recall that a healthy rectifying junction does NOT behave like a simple resistor. • Think about whether a working crystal should show symmetrical or asymmetrical resistance readings when you swap the meter leads. • Eliminate any choice that would also be true of a plain resistor (non-rectifying) when checked with an ohmmeter.