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Power - Pentode (NOT beam) ·Pentode-Pentode

QP25

Battery double-pentode output valve for quiescent push-pull audio service, combining two matched power pentode sections in one envelope.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
-
Base pins
7
Nominal heater
2 V / 200 mA

Description

Battery double pentode output valve for quiescent push-pull audio service, combining two matched power pentode sections in one envelope.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
7
Nominal heater voltage
2 V
Nominal heater current
200 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

2 physical sections, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.003 S
Max plate voltage
120 V
Max screen voltage
120 V

One representative section row for the matched repeated pentode sections.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.003 S
Max plate voltage
120 V
Max screen voltage
120 V

Second physical pentode section; added to align rows with SectionCount.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1960 Mazda

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Anode voltage

    110 V

    PushPull

  • Screen voltage

    110 V

    PushPull