🔍 Key Concepts

• Class B amplifier operation – how conduction angle and bias affect current and efficiency • Over‑excitation of the grid – what happens when grid drive is stronger than required for normal operation • Relationships among grid current, plate current, efficiency, and distortion in vacuum‑tube amplifiers

💭 Think About

• When you drive a Class B amplifier harder than its normal operating point, which currents in the tube tend to increase first: grid current, plate current, or both? • How does pushing the tube beyond its linear region affect the waveform shape at the plate – more or less distortion? • If currents are becoming excessive due to over‑drive, does that normally improve or degrade plate efficiency?

✅ Before You Answer

• Be clear on what Class B bias means (conduction for about half the cycle) and what happens if you over‑drive from that point. • Review how excessive grid current and excessive plate current each show up as symptoms of over‑excitation. • Decide whether distortion typically increases or decreases when an amplifier is driven beyond its linear range.