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Voltage - Triode (single) ·Triode

X99

Raytheon directly heated triode for detector or amplifier service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
4D
Socket code
UX4
Base pins
4
Nominal heater
3.3 V / 63 mA

Description

X99 is a Raytheon directly heated triode intended for detector or amplifier service.

Socket description

Medium-shell UX 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
4D
Socket code
UX4
Base pins
4
Nominal heater voltage
3.3 V
Nominal heater current
63 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

4D - 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
15500 Ω
Transconductance
0.000425 S
Amplification factor
6.6
Max plate voltage
120 V

Low-mu Class A triode.

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

1937 Raytheon Radio Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Filament voltage

    3 V

    Published filament rating

  • Filament current

    60 mA

    Published filament rating

  • Plate resistance

    15500 ohm

    ClassA

  • Transconductance

    425 µS

    ClassA

  • Amplification factor

    6.6

    ClassA

Other

  • Maximum plate voltage

    120 V

    Published datasheet rating

  • Plate voltage

    90 V

    ClassA

  • Control-grid bias

    4.5 V

    ClassA

  • Plate current

    2.5 mA

    ClassA

  • Biased-detector plate voltage

    80 V

    BiasedDetector

  • Biased-detector grid bias

    10.5 V

    BiasedDetector

  • Biased-detector no-signal plate current

    0.2 mA

    BiasedDetector

  • Grid-leak detector plate voltage

    45 V

    GridLeakDetector

  • Grid-leak resistance minimum

    0.25 MOhm

    GridLeakDetector

  • Grid-leak resistance maximum

    5 MOhm

    GridLeakDetector

  • Grid condenser

    0.00025 uF

    GridLeakDetector

Capacitance

  • Input capacitance

    2.5 pF

    Published capacitance

  • Output capacitance

    2.5 pF

    Published capacitance

  • Grid-to-plate capacitance

    3.3 pF

    Published capacitance

Data set 02

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Transconductance

    425 µS

    Published

  • Amplification factor

    6.6

    Published

  • Plate resistance

    15500 ohm

    Published

  • Filament voltage

    3 to 3.3 V

    Published operating range

  • Filament current

    60 mA to 63 mA

    Published operating range

  • Base difference

    Small 4-pin

    V99 uses Small 4-Nub; X99 uses Small 4-Pin

Capacitance

  • Grid-to-plate capacitance

    3.3 pF

    Published

  • Grid-to-filament capacitance

    2.5 pF

    Published

  • Plate-to-filament capacitance

    2.5 pF

    Published

Data set 03

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Input capacitance

    2.5 pF

  • Output capacitance

    2.5 pF

  • Grid-to-plate capacitance

    3.3 pF

Other

  • Plate voltage

    90 V

    ClassA

  • Grid voltage

    -4.5 V

    ClassA

  • Plate current

    2.5 mA

    ClassA

Characteristic

  • Plate resistance

    15500 ohm

    ClassA

  • Transconductance

    425 uS

    ClassA

  • Amplification factor

    6.6

    ClassA