6DQ5
The RCA 6DQ5 is a beam power pentode with an octal base. The plate connection is a top cap.
It is used in the Armstrong power oscillator of the 560.
- RCA 6DQ5 Datasheet (PDF)
- https://www.radiomuseum.org/tubes/tube_6dq5.html 6DQ5] @ radiomuseum.org