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Tube cross-reference

QQE025 alternatives, equivalents, and replacements

Review exact electrical variations and directional substitutions recorded for the QQE025 voltage dual tetrode. Compare core specifications and verify every restriction before using a replacement.

Exact variations of QQE025

These designations belong to the same electrical variation group. Their names may differ because of international standards, manufacturing tolerances, or materials, but they are recorded as electrically equivalent—not merely substitutes.

  • 6939

    Power - Pentode (NOT beam)

    Base
    9HL
    Socket
    B9A
    Base pins
    9
    Sections
    2
    Heater voltage
    12.6 V
    Heater current
    0.3 A

Verify before substituting

Matching a base or heater voltage is not enough to prove that two tubes are interchangeable. Check pin connections, heater current, maximum ratings, bias requirements, warm-up behavior, and the equipment manufacturer’s service documentation before making a substitution.

View the complete QQE025 specifications →