A plate choke in a Heising modulator:

🔍 Key Concepts

• Heising (constant-current) modulation basics and what part of the circuit supplies DC versus audio to the RF amplifier plate • The role of a plate choke (RF/audio choke) in separating DC from AC (audio) components • How plate modulation is achieved in high‑level AM transmitters (location of the audio in the plate circuit)

💭 Think About

• Think about whether a choke is normally used to build up or store audio voltage, or whether it mainly carries DC and blocks/smooths AC at certain frequencies • In a Heising modulator, where is the audio signal actually developed and applied — across which component(s) in the plate circuit? • Ask yourself: does the choke directly feed audio to the RF amplifier plate, or does it mainly allow DC plate current while causing the audio to appear elsewhere in the circuit?

✅ Before You Answer

• Verify what a choke’s primary function is in a modulation circuit: handling DC current while presenting high impedance to AC (audio/RF) • Check a basic Heising modulation schematic and identify which component has audio voltage across it (the modulation capacitor vs. the choke vs. the RF amplifier plate) • Confirm whether the plate choke’s job is to develop audio voltage or to provide a nearly constant DC current path for the modulated RF stage

A plate choke in a Heising modulator:

Builds up audio modulating voltages

Feeds audio modulating voltages to the plate of the RF modulated amplifier to produce plate modulation

A and B

None of the above

🔍 Key Concepts

💭 Think About

✅ Before You Answer