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Voltage Radio Detector Converter ·Pentode-Triode

PCF87

Variable-mu frame-grid triode-pentode designed for VHF television tuner frequency-changing and high-frequency front-end service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
B9A
Socket code
B9A
Base pins
9
Nominal heater
7.4 V / 300 mA

Description

Variable-mu frame-grid triode-pentode for VHF television tuners. The supplied English-language Mazda/Thorn-AEI datasheet was used for the technical and descriptive extraction.

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
7.4 V
Nominal heater current
300 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
Max plate voltage
250 V
Max screen voltage
230 V
Max plate dissipation
2 W
Max screen dissipation
0.5 W
Max cathode current
18 mA

Published ratings and characteristics promoted where clearly stated; identical repeated sections compressed when applicable.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0085 S
Amplification factor
20
Max plate voltage
250 V
Max plate dissipation
2 W
Max cathode current
18 mA

Published ratings and characteristics promoted where clearly stated; identical repeated sections compressed when applicable.

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 Current Ih

    3 A

  • Heater Voltage Vh

    74 V

  • Maximum Anode Dissipation pa(max) 20

    20 W

  • Maximum Anode Voltage Va(max) 250

    250 V

  • Maximum Heater to Cathode Voltage (R.M.S.) Vh-k(r.m.s.)max 200

    200 V

  • Maximum Cathode Current Ik(max) 18

    18 mA

  • Supply Voltage Vb 200

    200 V

  • TYPICAL OPERATION AS FREQUENCY CHANGER AT

    200 Mc/s

  • Supply Voltage Vb

    200 V

Characteristic

  • Grid 1 to all cg1_all 65 72

    81 pF

  • Anode Pentode to all Cap-all 28 30

    40 pF

  • Grid 1 to Anode Pentode cg1-ap 008 •01

    12 pF

  • Anode Triode to Earth cat-E 21 22

    30 pF

  • Grid Triode to Earth cgt_E 33 34

    42 pF

  • Anode Pentode to Grid Triode cap_gt •0015 0025

    4 pF

  • Grid Triode to Anode Triode cgt_at 19 20

    22 pF

  • Anode Pentode to Anode Triode cap-at 009 012

    15 pF

  • Grid 1 to Grid Triode cg1-gt 008 •016

    35 pF

  • Grid 1 to Anode Triode cg1_at •003 •0065 •

    11 pF

  • Anode Voltage Va 125

    100 V

  • Control Grid Voltage Vg1 -1.5

    -3.2 V

  • Anode Current la 10

    15 mA

  • Mutual Conductance gm 11

    8.5 mA

  • Frequency f 200

    36 Mc/s

  • Resistance, Ra=5.6k iZ) (approx.) Va 160

    130 V

  • Screen Grid Voltage (Rg2=27kS2) (approx.) Vg2 150

    100 V

  • Anode Current (approx.) la 7.3

    12.5 mA

  • Screen Grid Current (approx.) Ig2 1.8

    37 mA

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

    15 mA

  • reduction 10 : 1 Vg1(gm/1D)

    -4.8 V

  • reduction 100 : 1 Vg1(gm/100) —

    -66 V

  • cut off Lci„(W) —

    27 pF

  • Anode Voltage Va

    60 V

  • Anode Current la

    7 mA

  • Rectified Grid Voltage (Grid Resistance = 47k i2) Vg

    6 V

  • voltage of greater than

    8 V

  • Resistance, R5=5 6k f2) (approx.) Va 160

    130 V

  • Screen Grid Voltage (Rg2=27kc2) (approx.) Vg2 150

    100 V

  • Anode Current (approx.) la 73 i2

    5 mA

  • Screen Grid Current (approx.) Ig2 1 8

    37 mA

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

    15 mA

  • reduction 10 : 1 Vg1(gm/1oh) — —

    6 V

  • reduction 100 : 1 Vg1(gm/100)

    -8.3 V

  • cut off Ocin(W) —

    27 pF

  • Anode Voltage Va

    70 V

  • Anode Current la

    9 mA

  • Rectified Grid Voltage (Grid Resistance = 47k i2) Vg

    11 V

  • ■N.~

    1 A

  • Anode Voltage (Decoupling Resistance, Ra =5 6k4) Va

    155 V

  • Screen Grid Voltage (Rg2=39kt2) Vg2

    108 V

  • Anode Current (approx.) la

    81 mA

  • Screen Grid Current (approx.) Ig2

    24 mA

  • Conversion Conduction at 1 Mcls (Vhet(pk)=2 8V) gL

    49 mA

  • Anode Voltage Va

    100 V

  • Anode Current la

    5 mA