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Voltage - Triode (single high frequency) ·Triode

DC70

Directly heated subminiature UHF oscillator triode for compact high-frequency signal generation.

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

Description

The Mullard DC70 is a directly heated subminiature UHF triode intended mainly as a battery-operated oscillator around 500 MHz.

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
1.25 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
4000 Ω
Transconductance
0.0034 S
Amplification factor
14
Max plate voltage
150 V
Max plate dissipation
2.4 W
Max cathode current
20 mA

Promoted from clearly identified published ratings/characteristics; additional operating points, capacitances, rectifier conditions, and application-specific values are retained in TUBE_SECTION_PARAMETER.

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

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Filament Voltage

    1.25 V

    DCOnly

  • Filament Current

    200 mA

    DCOnly

  • Plate Voltage

    150 V

  • Plate Current

    14.5 mA

  • Transconductance

    3750 uS

  • Plate Resistance

    8300 ohm

  • Amplification Factor

    31 ratio

  • Grid-Plate Capacitance

    1.5 pF

    Shielded

  • Input Capacitance

    1.3 pF

    Shielded

  • Output Capacitance

    1.9 pF

    Shielded

Other

  • Intended Oscillator Frequency

    500 MHz

    Approximate

Data set 02

1963 Philips Electron Tubes Handbook V1

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid-to-plate capacitance

    1.4 pF

    Section1

  • Grid-to-filament capacitance

    1.3 pF

    Section1

  • Plate-to-filament capacitance

    1.9 pF

    Section1

Other

  • Plate voltage

    150 V

    UHF

  • Plate current

    12 mA

    UHF

  • Control-grid voltage

    -4.5 V

    UHF

  • Oscillator frequency

    500 MHz

    Oscillator

  • Oscillator plate voltage

    150 V

    Oscillator

  • Oscillator cathode current

    20 mA

    Oscillator

  • Oscillator output power

    450 mW

    Oscillator

Characteristic

  • Transconductance

    3400 µS

    Section1

  • Amplification factor

    14

    Section1

  • Plate resistance

    4000 Ω

    Section1

  • Expected intermittent operating life approximately

    200 h

    SpecifiedOscillatorOperation

Data set 03

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • at

    500 Mc/s

    Published datasheet condition

  • at 500 Mc/s (A

    60 cm

    Published datasheet condition

  • at 500 Mc/s (A = 60 cm) is about

    450 mW

    Published datasheet condition

  • The filament voltage of the DC 70 is

    1.25 V

    Published datasheet condition

  • a current of

    200 mA

    Published datasheet condition

  • mutual conductance is high (

    3.4 mA

    Published datasheet condition

  • current of

    12 mA

    Published datasheet condition

  • Filament voltage. . . . . . V;, —

    1.25 V

    Published datasheet condition

  • Filament current. . . . . . J; = o

    200 mA

    Published datasheet condition

  • Anode to grid . . . . . . C,,

    1.4 pF

    Published datasheet condition

  • Grid to filament . . . . . C,

    1.3 pF

    Published datasheet condition

  • Anode to filament . . . . . C,

    1.9 pF

    Published datasheet condition

  • Note: Direct soldered connections to the leads of the tube must be at least

    5 mm

    Published datasheet condition

  • from the seal, and any bending of the tube leads must be at least

    1.5 mm

    Published datasheet condition

  • Anode voltage Ve

    150 V

    Published datasheet condition

  • Grid voltage . Vo =—=—

    45 V

    Published datasheet condition

  • Anode current I,

    12 mA

    Published datasheet condition

  • Mutual conductance . §

    34 mA

    Published datasheet condition

  • Anode voltage . . . . . . V,

    150 V

    Published datasheet condition

  • Cathode current . . . . . . I,

    20 mA

    Published datasheet condition

  • Output power . . . . . . W, =— o

    45 W

    Published datasheet condition

Other

  • Anode voltage . . . . . . V, —

    150 V

    Published datasheet condition

  • Anode dissipation . . . . . W,

    24 W

    Published datasheet condition

  • Cathode current . . . . . . I, —

    20 mA

    Published datasheet condition

  • Grid current . . . . . . . I,

    5 mA

    Published datasheet condition

  • Filament voltage. . . . . . V

    1.35 V

    Published datasheet condition