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Voltage Radio Detector Converter ·Pentode

CF1

All-current high-frequency pentode for RF, IF, audio-frequency amplification, and detector service. High plate resistance provides useful gain across several receiver functions in universal and series-heater equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
P8A
Base pins
8
Nominal heater
13 V / 200 mA

Description

All-current high-frequency pentode for RF, IF, audio amplifier, and detector service.

Socket description

European 8-pin side-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
P8A
Base pins
8
Nominal heater voltage
13 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
400000 Ω
Transconductance
0.0023 S
Max plate voltage
250 V
Max plate dissipation
1 W
Max cathode current
6 mA

Published operating point, characteristic values and capacitance column reviewed.

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

1938 Philips Miniwatt Vacuum Tube Catalog

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate voltage

    200 V

    Published table operating point

  • Plate current

    3 mA

    Published table operating point

  • Control-grid bias

    2 V

    Published table operating point

  • Screen voltage

    100 V

    Published table operating point

  • Screen current

    0.9 mA

    Published table operating point

Characteristic

  • Transconductance

    2300000 µS

    Published table characteristic

  • Plate resistance

    400000 ohm

    Published table characteristic

  • Heater/filament voltage

    13 V

    Published heater/filament rating

  • Heater/filament current

    200 mA

    Published heater/filament rating

Capacitance

  • Grid-to-plate capacitance

    0.003 pF

    Published table capacitance

Data set 02

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • Maximum transconductance

    3200 µS

Other

  • Typical plate current

    3 mA

  • Maximum screen dissipation

    0.3 W