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Voltage Radio Detector Converter ·Pentode-Triode

ECF805

Frame-grid triode and variable-mu pentode for television tuner frequency-changing and controlled IF-amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
B9A
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 350 mA

Description

Frame-grid triode variable-mu pentode for television tuner frequency-changer and IF service. Technical and descriptive data are taken from the supplied English-language Mazda/Thorn-AEI datasheet.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B9A
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
350 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B9A - 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

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.011 S
Amplification factor
50
Max plate voltage
250 V
Max plate dissipation
2 W
Max screen dissipation
0.5 W
Max cathode current
18 mA

Published ratings and characteristics promoted from the approved English source.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0055 S
Amplification factor
17
Max plate voltage
250 V
Max plate dissipation
2 W
Max cathode current
15 mA

Published ratings and characteristics promoted from the approved English 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

1973 Mazda Valves Binder 2

Published operating points and test conditions from this source.

SECTION 2

Triode

Other

  • Heater Voltage Vh

    6.3 V

  • Heater Current Ih

    35 A

  • Maximum Anode Dissipation pa(max) 2

    2 W

  • Maximum Anode Voltage Va(max) 250

    250 V

  • Maximum Heater to Cathode Voltage (D.C.) Vh-k(max) 150

    150 V

  • Maximum Cathode Current Ik(max) 18

    15 mA

Characteristic

  • Grid 1 to all Cg1-a I I 6.7 7.1

    8.2 pF

  • Anode Pentode to all Cap-a I I 2.7 3.1

    4.2 pF

  • Grid 1 to Anode Pentode Cg1 _ap •007 -008

    9 pF

  • Anode Triode to Earth Cat-E 2.2 2.5

    3.5 pF

  • Grid Triode to Earth Cgt-E 2.6 2.7

    3.7 pF

  • Anode Pentode to Grid Triode Cap gt •001 •003 •

    5 pF

  • Grid Triode to Anode Triode Cgt-at 2.0 2.05

    2.1 pF

  • Anode Pentode to Anode Triode Cap-at 014 027

    46 pF

  • Grid 1 to Grid Triode Cg1_gt -008 018 •

    37 pF

  • Grid 1 to Anode Triode Cg1-at •002 •004 •

    6 pF

  • Anode Voltage Va 125

    100 V

  • Control Grid Voltage Vg1 —1 5 —

    3 V

  • Anode Current la 10

    14 mA

  • Mutual Conductance gm 11

    5.5 mA

  • Supply Voltage Vb 200

    200 V

  • Anode Voltage (Decoupling Resistance, R3=5 6k0) (approx) V, 155

    125 V

  • Screen Grid Voltage (Rg2=27kQ) (approx) Vg2 135

    92 V

  • Anode Current (approx) la 78

    132 mA

  • Screen Grid Current (approx) Ig2 24

    40 mA

  • Conversion Conductance at 1 Mc/s (Vb,Ra,Rg1,Rg2 as above) g

    47 mA

  • Mutual Conductance (Vb,Ra,Rg1,Rg2 as above) gm —

    152 mA

  • Grid Voltage for Mutual Conductance reduction 10 : 1 Vg1(gm/10) —

    50 V

  • Grid Voltage for Mutual Conductance reduction 100 : 1 Vg1(gm/1oo) —

    68 V

  • Change in Input Capacitance by biasing valve to cut-off tin(w) —

    28 pF

  • Anode Voltage Va

    77 V

  • Anode Current la

    78 mA

  • Rectified Grid Voltage (Grid Resistance=47kf2) Vg

    65 V

  • greater than

    8 V

  • Anode Voltage (Decoupling Resistance, Ra=5 6k S2) approx Va 160

    125 V

  • Screen Grid Voltage (Rg2=27kf2) approx Vg2 140

    92 V

  • Anode Current (approx) la 70

    132 mA

  • Screen Grid Current (approx) Ig2 22

    40 mA

  • Mutual Conductance (Vb,Ra,Rg1 ,Rg2 as above) gm —

    152 mA

  • Grid Voltage for Mutual Conductance reduction 10 : 1 Vg1(g mJ10) — —

    62 V

  • Grid Voltage for Mutual Conductance reduction 100 : 1 Vg1(gm/100) — —

    85 V

  • Change in Input Capacitance by biasing valve to cut-off Ocin(w) —

    28 pF

  • Anode Voltage Va

    110 V

  • Anode Current la

    105 mA

  • Rectified Grid Voltage (Grid Resistance=47kQ) Vg

    11 V