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

ECH21

Triode-heptode frequency changer for superheterodyne receivers. The triode generates local oscillation while the heptode mixes it with the incoming station signal to produce the intermediate frequency.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
Loctal
Socket code
B8G
Base pins
8
Nominal heater
6.3 V / 320 mA

Description

Triode-heptode frequency changer with heptode mixer and triode RF oscillator sections.

Socket description

Loctal 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
Loctal
Socket code
B8G
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
320 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Loctal - 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

Heptode

X-ray radiationInterelectrode capacitances
Plate resistance
1400000 Ω
Max plate voltage
250 V
Max screen voltage
100 V

Published maximum ratings/characteristics promoted from source.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0017 S
Amplification factor
22
Max plate voltage
250 V
Max plate dissipation
1.5 W

Published maximum ratings/characteristics promoted from 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

Heptode

Characteristic

  • Conversion Conductance

    750 uA/V

    Mixer

SECTION 2

Triode

Characteristic

  • Heater Voltage

    6.3 V

  • Heater Current

    300 mA

Data set 02

195X Tesla

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    320 mA

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Screen Voltage

    100 V

SECTION 2

Triode

Other

  • HeaterVoltageNominal

    6.3 V

    Nominal

  • HeaterCurrentNominal

    320 mA

    Nominal

  • Maximum Plate Voltage

    250 V

  • Maximum Plate Dissipation

    1.5 W

Characteristic

  • Transconductance

    1700 µS

    Typical

  • Amplification Factor

    22

    Typical

Data set 03

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 2

Triode

Characteristic

  • kgssf

    1 ma

    Published datasheet value

Capacitance

  • Cgv

    6.5 pF

    Published datasheet value

  • Cgv = 6,5 pF Cg

    3.8 pF

    Published datasheet value

  • Cg

    8 pF

    Published datasheet value

  • Cg = 8 pF Coa

    3.1 pF

    Published datasheet value

  • Cagy1 <

    0.002 pF

    Published datasheet value

  • Cagy1 <0,002 pF Cag

    1.1 pF

    Published datasheet value

  • Cg}

    8 pF

    Published datasheet value

  • Cg} = 8 pF Cgk

    2.7 pF

    Published datasheet value

  • Cg1g3<

    0.3 pF

    Published datasheet value

  • Cg1g3< 0,3 pF Cak

    1.6 pF

    Published datasheet value

  • Cg1f <

    0.007 pF

    Published datasheet value

  • Cg1f <0,007 pF Cge <

    0.1 pF

    Published datasheet value

  • Cng1B <

    0.1 pF

    Published datasheet value

  • Cgr+g3)g1m <

    0.35 pF

    Published datasheet value

  • C(gT+g3)an < O»

    1 pF

    Published datasheet value

Other

  • Va=Vp

    250 v

    Published datasheet value

  • Vg1 = -7

    -24.5 v

    Published datasheet value

  • Vg2+gs = 100

    250 v

    Published datasheet value

  • Se = 750

    7.5 w

    Published datasheet value

  • Vg3

    0 v

    Published datasheet value

  • Vg1 = ‘-2 ~36

    -44 v

    Published datasheet value

  • Vgo+gs = 90

    250 v

    Published datasheet value

  • 3 = 2200 22

    2.2 w

    Published datasheet value

  • Va

    100 V

    Published datasheet value

  • Ian

    12 mA

    Published datasheet value

  • Vy

    250 V

    Published datasheet value

  • Ia = 4 H

    5 mA

    Published datasheet value

  • Seff

    0.55 mA/V

    Published datasheet value

  • Vao

    550 V

    Published datasheet value

  • Vs

    300 V

    Published datasheet value

  • Wa

    1.5 W

    Published datasheet value

  • V{g2+gd)do

    550 V

    Published datasheet value

  • Vgoigalla

    3 mA

    Published datasheet value

  • Vgoigalla = 3 mA}

    100 V

    Published datasheet value

  • V82,54(I3 <.t mA)

    3000 V

    Published datasheet value

  • Vg1 (Ig1=+

    0.3 w

    Published datasheet value

  • Vg1 (Ig1=+0,3 wA)

    -1.3 V

    Published datasheet value

  • Vg3 (Ig3=+

    0.3 w

    Published datasheet value

  • Vg3 (Ig3=+0,3 wh)

    -1.3 V

    Published datasheet value

  • Ik

    15 mA

    Published datasheet value

  • Vex

    50 v

    Published datasheet value

  • Vg (Ig:#O,B uh) = max. —

    1 v

    Published datasheet value