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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

PTT208P

Long-life power pentode for professional low-frequency output stages, co-designated with R147.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
18 V / 140 mA

Description

Long-life power-amplifier pentode for low-frequency output stages.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
18 V
Nominal heater current
140 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
140000 Ω
Transconductance
0.006 S
Max plate voltage
225 V
Max screen voltage
225 V
Max plate dissipation
4 W
Max screen dissipation
0.8 W

Published ratings and characteristics promoted from the approved source.

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

1953 La Radiotechnique

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • HeaterVoltageNominal

    18 V

    Nominal

  • HeaterCurrentNominal

    140 mA

    Nominal

  • Maximum Plate Voltage

    225 V

  • Maximum Screen Voltage

    225 V

  • Maximum Plate Dissipation

    4 W

  • Maximum Screen Dissipation

    0.8 W

Characteristic

  • Transconductance

    6000 µS

    Typical

  • Amplification Factor

    840

    Typical

  • Plate Resistance

    140000 ohm

    Typical