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Power - Triode Single (under 10W) ·Triode

8727

Fast-warm-up ceramic-metal high-mu triode for linear RF amplification, oscillator, doubler, and tripler service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B9A
Base pins
9
Nominal heater
6.3 V / 225 mA

Description

Fast-warm-up ceramic-metal high-mu triode for linear RF, oscillator, doubler, and tripler service.

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

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
4375 Ω
Transconductance
0.016 S
Amplification factor
70
Max plate voltage
250 V
Max plate dissipation
2.5 W
Max cathode current
25 mA

Plate resistance derived from published μ=70 and gm=16000 µS.

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

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater/filament voltage

    6.3 V

  • Heater/filament current

    225 mA

  • Maximum plate voltage

    250 V

  • Maximum cathode current

    25 mA

  • Plate dissipation

    2.5 W

  • Useful power output

    2.2 W

    LinearRF

  • Frequency doubler output

    1.3 W

    ClassC

  • Frequency tripler output

    0.7 W

    ClassC

Characteristic

  • Amplification factor

    70

  • Transconductance

    16000 uS

    Plate125V;CathodeResistor50ohm;14mA

  • Plate resistance

    4375 ohm

    DerivedFromPublishedMuAndGm

Capacitance

  • Grid-to-plate capacitance

    2.1 pF

  • Grid-to-cathode/heater capacitance

    4.4 pF

  • Plate-to-cathode/heater capacitance

    0.04 pF

    Maximum