The cathode of an indirectly heated type of...

Question 1 / 27070KH7puucVwQKJJ5Vvz98i

Question 1 of 27070KH7puucVwQKJJ5Vvz98i

The cathode of an indirectly heated type of vacuum tube should be maintained at nearly the same potential as the heater circuit:

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Question 1 of 27070

The cathode of an indirectly heated type of vacuum tube should be maintained at nearly the same potential as the heater circuit:

🔍 Key Concepts

• Indirectly heated cathode construction in vacuum tubes (separate heater and cathode sleeves) • Electrical potential difference and its effect on insulation stress • How AC heater voltage can introduce hum into the signal path

💭 Think About

• How does a large voltage difference between heater and cathode affect the thin insulation between them? • If the heater is powered by AC, what happens when its voltage is far from the cathode’s voltage in terms of induced hum? • Would matching potentials help one, both, or neither of these issues?

✅ Before You Answer

• Review how an indirectly heated cathode is physically built (heater inside a cathode sleeve with insulation between). • Consider the effect of high heater-to-cathode voltage on both insulation breakdown and unwanted coupling of AC into the cathode. • Check which options address electrical stress versus signal hum and whether both can be valid at the same time.

Question 1 of 27070

The cathode of an indirectly heated type of vacuum tube should be maintained at nearly the same potential as the heater circuit:

To reduce hum pickup into the cathode

To prevent breakdown of the insulation between the heater and cathode

A & B

None of the above