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Voltage Dual Pentode ·Pentode-Pentode

6MK8A

Dissimilar pentode pair for television sync separation, clipping, AGC, and low-level color-demodulator circuits, integrating several pulse and chroma-processing functions.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
9F6
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 300 mA

Description

Miniature type used in sync-separator, clipper, age, 18 an<* low-level color-demodulator circuits in television « °spi receivers. Outlines section, 6E; requires miniature 9- 9F6 contact socket.

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
9F6
Socket code
B9A
Base pins
9
Nominal heater voltage
6.3 V
Nominal heater current
300 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

9F6 - 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
Plate resistance
6250 Ω
Transconductance
0.0075 S
Max plate voltage
300 V
Max screen voltage
67.5 V
Max plate dissipation
1.1 W
Max cathode current
32 mA

Full supplied entry reviewed for ratings, characteristics, operating data, and capacitances.

Section 2

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
6250 Ω
Transconductance
0.0075 S
Max plate voltage
300 V
Max screen voltage
67.5 V
Max plate dissipation
1.1 W
Max cathode current
32 mA

Second physical pentode restored under one-row-per-physical-section policy; duplicated from reviewed section specification.

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

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater Voltage

    6.3 volts

    Published value from supplied target entry

  • Heater Current

    0.3 ampere

    Published value from supplied target entry

  • Plate Voltage (Each Unit)

    300 volts

    Published value from supplied target entry

  • Grid-No

    3

    Published value from supplied target entry

  • Grid-No

    150 volts

    Published value from supplied target entry

  • Grid-No.l (Control-Grid) Voltage, Negative-bias value

    50 volts

    Published value from supplied target entry

  • Cathode Current

    32 mA

    Published value from supplied target entry

  • Plate Dissipation (Each Section)

    1.1 watts

    Published value from supplied target entry

  • Grid-No

    0.75 watt

    Published value from supplied target entry

  • MAXIMUM PLATE CURRENT RATIO (Balance)

    1

    Published value from supplied target entry

  • Plate Voltage

    100

    Published value from supplied target entry

  • Grid-No

    67.5 volts

    Published value from supplied target entry

  • Grid-No.l Voltage

    67.5 volts

    Published value from supplied target entry

  • Grid-No

    0 volts

    Published value from supplied target entry

  • Grid-No.l Resistance

    0.68 megohm

    Published value from supplied target entry

  • Plate Voltage

    100 volts

    Published value from supplied target entry

  • Grid-No.l Voltage

    0 volts

    Published value from supplied target entry

  • Plate Current —

    2 mA

    Published value from supplied target entry

  • Grid-No

    1

    Published value from supplied target entry

  • Grid-No

    2

    Published value from supplied target entry

  • Plate Current (Each Section) —

    2 mA

    Published value from supplied target entry

  • Cathode Current

    8.5 mA

    Published value from supplied target entry

  • Grid-No

    4.4 mA

    Published value from supplied target entry

  • Grid-No

    0.5 megohm

    Published value from supplied target entry

  • Grid-No.l-Circuit Resistance

    0.5 megohm

    Published value from supplied target entry

  • With plate and grid No

    100

    Published value from supplied target entry

  • Heater Voltage

    9.6 volts

    Published value from supplied target entry

  • Plate Voltage

    330 volts

    Published value from supplied target entry

  • Grid Voltage, Positive-bias valu

    0 volt

    Published value from supplied target entry

  • Plate Voltage

    200 volts

    Published value from supplied target entry

  • Amplification Factor

    40

    Published value from supplied target entry

  • Plate Resistance (Approx.)

    10000 ohms

    Published value from supplied target entry

  • Transconductance

    4000 mhos

    Published value from supplied target entry

  • Plate Current

    4.8 mA

    Published value from supplied target entry

  • Grid Voltage (Approx.) for plate current f

    -11 volts

    Published value from supplied target entry

  • Heater Voltage (ac/dc)

    6.3 volts

    Published value from supplied target entry

  • Heater Current

    0.535 ampere

    Published value from supplied target entry

  • Heater Warm-up Time

    11 seconds

    Published value from supplied target entry

Capacitance

  • Direct Interelectrode Capacitances Unit No.l Unit No

    3

    Published value from supplied target entry

  • Grid to Plate

    2.6 pF

    Published value from supplied target entry

  • Grid to Cathode and Heater

    4.6 PF

    Published value from supplied target entry

  • Plate to Cathode and Heater

    0.65 PF

    Published value from supplied target entry