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Voltage - Triode (with diode, heptode or hexode) ·Hexode-Triode

ECH35

Triode-hexode frequency changer for superheterodyne receivers. The triode supplies local-oscillator excitation while the hexode performs frequency conversion with reduced interaction between oscillator and signal circuits.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
Octal
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 300 mA

Description

Triode-hexode frequency changer for AC mains receivers; the hexode section is arranged for automatic gain control.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
Octal
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Octal - 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

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0028 S
Amplification factor
24
Max plate voltage
100 V
Max plate dissipation
1.5 W

Published Mullard ratings and characteristics promoted from the supplied source.

Section 2

Hexode

X-ray radiationInterelectrode capacitances
Plate resistance
1300000 Ω
Max plate voltage
300 V
Max screen voltage
125 V
Max plate dissipation
1.2 W
Max screen dissipation
0.6 W
Max cathode current
15 mA

Published Mullard ratings and characteristics promoted from the supplied 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

1951 Mullard Valve and Service Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater Voltage

    6.3 V

  • Heater Current

    300 mA

SECTION 2

Hexode

Characteristic

  • VariableMuCharacteristic

    1 boolean

    FrequencyChanger

Data set 02

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater Voltage

    6.3 V

  • Heater Current

    300 mA

  • Transconductance

    2800 uS

    OscillatorSection

  • Amplification Factor

    24 ratio

    OscillatorSection

  • Transconductance

    2200 uS

    OscillatorSection; At250V

  • Grid-Cathode Capacitance

    9 pF

    TriodeSection

  • Plate-Cathode Capacitance

    3 pF

    TriodeSection

  • Plate-Grid Capacitance

    1.6 pF

    TriodeSection

Other

  • Plate Voltage

    100 V

    OscillatorSection

  • Plate Current

    10 mA

    OscillatorSection

  • Plate Voltage

    250 V

    OscillatorSection; With45kPlateResistor

  • Plate Current

    4.5 mA

    OscillatorSection; With45kPlateResistor

SECTION 2

Hexode

Other

  • Plate Voltage

    250 V

    FrequencyChanger; FixedScreenVoltage

  • Screen Voltage

    100 V

    FrequencyChanger; FixedScreenVoltage

  • Plate Current

    3 mA

    FrequencyChanger; MaximumGainPoint

  • Screen Current

    3 mA

    FrequencyChanger; MaximumGainPoint

  • Grid Voltage

    -2 V

    FrequencyChanger; MaximumGainPoint

  • Grid Voltage

    -17 V

    FrequencyChanger; ReducedGain

  • Grid Voltage

    -23 V

    FrequencyChanger; LowGain

  • Maximum Plate Voltage

    300 V

    HexodeSection

  • Maximum Plate Dissipation

    1.2 W

    HexodeSection

  • Maximum Screen Voltage

    125 V

    HexodeSection

Characteristics

  • Conversion Transconductance

    650 uS

    FrequencyChanger; MaximumGainPoint

  • Plate Resistance

    1300000 ohm

    FrequencyChanger

  • Grid-Cathode Capacitance

    5 pF

    HexodeSection

  • Plate-Grid Capacitance

    0.008 pF

    HexodeSection; Maximum

Data set 03

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate supply voltage

    250 V

    Oscillator

  • Plate current

    3.3 mA

    Oscillator

  • Maximum plate voltage

    100 V

  • Maximum plate dissipation

    1.5 W

Characteristic

  • Plate voltage

    100 V

  • Plate current

    10 mA

    Vg=0

  • Transconductance

    2.8 mA/V

    Vg=0

  • Amplification factor

    24

    Vg=0

Capacitance

  • Grid-to-cathode capacitance

    9 pF

  • Anode-to-cathode capacitance

    3 pF

  • Anode-to-grid capacitance

    1.6 pF

SECTION 2

Hexode

Other

  • Plate voltage

    250 V

    FrequencyChanger

  • Screen-grid voltage

    100 V

    FrequencyChanger

  • Control-grid voltage

    -2 V

    FrequencyChanger

  • Plate current

    3 mA

    FrequencyChanger

  • Screen-grid current

    3 mA

    FrequencyChanger

  • Conversion conductance

    650 uA/V

    FrequencyChanger

  • Plate resistance

    1.3 MOhm

    FrequencyChanger

  • Maximum plate voltage

    300 V

  • Maximum plate dissipation

    1.2 W

  • Maximum screen-grid voltage

    125 V

    Ia=4.5mA

  • Maximum screen-grid dissipation

    0.6 W

  • Maximum cathode current

    15 mA

Capacitance

  • Control-grid to cathode capacitance

    5 pF

  • Anode-to-cathode capacitance

    10 pF

Data set 04

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Chauffage: indirect par C.A. ou C.C.; Ve

    6.3 V

    Published datasheet value

Capacitance

  • Cg1

    5 pF

    Published datasheet value

  • Cg1 = 5,0 pF cgT

    9 pF

    Published datasheet value

  • CaH

    10 pF

    Published datasheet value

  • CaH = 10 pF CaT

    3 pF

    Published datasheet value

  • CaH—g1 <

    0.003 pF

    Published datasheet value

  • CaH—g1 < 0,003 pF caT—gT

    1.6 pF

    Published datasheet value

  • Cg1f <

    0.001 pF

    Published datasheet value

  • Cg1f < 0,001 pF cgT—g1H <

    0.3 pF

    Published datasheet value

Other

  • Vb = 100 150

    250 v

    Published datasheet value

  • aT+g3 200 200

    200 w

    Published datasheet value

  • Ia = 3,3 8

    3.3 mA

    Published datasheet value

  • Vose = 8 8

    8 V

    Published datasheet value

  • Vazvb = 100 200

    250 v

    Published datasheet value

  • Se = 450 4,5 650 6,5 650

    6.5 µA

    Published datasheet value

  • Vao = max

    550 V

    Published datasheet value

  • Vg = max

    300 V

    Published datasheet value

  • Vg = max

    1.2 W

    Published datasheet value

  • V(go+g4) = max

    550 V

    Published datasheet value

  • g?+g43Ia <

    0.5 mA

    Published datasheet value

  • g?+g43Ia < 0,5 mAg = max

    200 V

    Published datasheet value

  • go+g4{Iy <

    4.5 mA

    Published datasheet value

  • go+g4{Iy < 4,5 mA = max

    125 V

    Published datasheet value

  • go+ga = max

    0.6 W

    Published datasheet value

  • Vg1{Ig1 = +0,3 uh) = max

    -1.3 V

    Published datasheet value

  • Vg3(Ig3 = +

    0.3 w

    Published datasheet value

  • Vg3(Ig3 = +0,3 wA) = max

    -1.3 V

    Published datasheet value

  • I = max

    15 mA

    Published datasheet value

  • Vit = max

    100 V

    Published datasheet value

  • a = max

    150 V

    Published datasheet value

  • Vg(lg = +0,3 pa) = max

    -1.3 V

    Published datasheet value

  • Wg = max

    1.5 V

    Published datasheet value