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Voltage Pentode ·Pentode

4067

Directly heated subminiature electrometer pentode designed specifically for pH meters and other extremely high-impedance measurement circuits.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B8D
Base pins
8
Nominal heater
0.5 V / 8 mA

Description

Directly heated subminiature electrometer pentode intended for pH meters.

Socket description

Subminiature 8-lead

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B8D
Base pins
8
Nominal heater voltage
0.5 V
Nominal heater current
8 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
Max plate voltage
45 V
Max screen voltage
45 V

Philips 4067 directly heated subminiature electrometer pentode for pH meters and extremely high-impedance measurement, 0.5 V, 8 mA DC filament; filament current must be adjusted to 8 mA. Manufacturer explicit maximum anode voltage 45 V and grid-2 screen voltage 45 V. Typical circuit: 12 V anode supply, screen 21 V, plate current around 0.5 µA, control grid about -1.7 ±0.5 V, external 20 MΩ load. Very high cold control-grid insulation; guard against contamination and leakage. Apply filament voltage BEFORE anode voltage, do not remove protective glass envelope until installed, and operate only in complete darkness with light-tight screening. Solder leads at least 5 mm from seal and bend no closer than 1.5 mm.

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

1957 Philips Receiving and Amplifying Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • HeaterOrFilamentVoltage

    0.5 V

  • HeaterOrFilamentCurrent

    8 mA

  • Grid1 Voltage

    -1.7 V

    Typical

Other

  • BatteryVoltage

    12 V

    pHMeter

  • Grid2 Voltage

    21 V

    pHMeter

  • Plate Current

    0.5 uA

    pHMeter

Data set 02

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Chauffage: direct par C.C. Ie

    8 mA

    Chauffage: direct par C.C. Ie = 8 mA

  • The heater current should be adjusted to

    8 mA

    The heater current should be adjusted to 8 mA

  • Le courant de chauffage sera réglé a

    8 mA

    Le courant de chauffage sera réglé a 8 mA

  • Der Heizstrom muss auf

    8 mA

    Der Heizstrom muss auf 8 mA eingestellt werden

  • Vg2

    21 v

    Vg2 = 21 v

  • Ra

    20 MΩ

    Ra = 20 MQ

  • Heating : direct by D.C. V¢

    0.5 V

    Heating : direct by D.C. V¢ 0,5V

  • Grenzdaten Va De

    45 v

    Grenzdaten Va De... 45 v