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Voltage - Triode (single high frequency) ·Triode

703A

Ultra-high-frequency triode with short direct leads and low capacitance for oscillator, amplifier, or mixer service to approximately 1500 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4B
Base pins
4
Nominal heater
1.15 V / 4.5 A

Description

Ultra-high-frequency triode with short direct leads, close electrode spacing, and low capacitance, suitable for oscillator, amplifier, or mixer service to frequencies as high as 1500 MHz.

Socket description

Medium 4-pin bayonet

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B4B
Base pins
4
Nominal heater voltage
1.15 V
Nominal heater current
4.5 A
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
Transconductance
0.002075 S
Max plate voltage
350 V
Max plate dissipation
20 W

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater voltage

    1.15 V

    Nominal

  • Heater current

    4.5 A

    Nominal

Capacitance

  • Grid-to-plate capacitance

    0.9 pF

    Direct electrode capacitance

  • Grid-to-filament capacitance

    0.85 pF

    Direct electrode capacitance

  • Plate-to-filament capacitance

    0.6 pF

    Direct electrode capacitance