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Rectifier - Damper Diode ·BeamPower-Diode

38HK7

Combined damper diode and beam-power horizontal-deflection amplifier, integrating high-current line-output and recovery-diode functions in a single television tube.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B12C
Base pins
12
Nominal heater
37.8 V / 450 mA

Description

38HK7 is a BeamPower vacuum tube documented in the RCA Receiving Tube Manual. The supplied excerpt was reviewed for heater or filament data, physical section arrangement, maximum ratings, electrical characteristics, capacitances, and stated application.

Socket description

Duodecar 12-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B12C
Base pins
12
Nominal heater voltage
37.8 V
Nominal heater current
450 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

2 physical sections, each with unique specifications.

Section 1

Diode

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
4200 V
Rectifier nominal output current
200 mA
Rectifier peak forward current
1.2 A
Rectifier forward voltage drop
21 V
Rectifier max heater-cathode voltage
4200 V
Rectifier warm-up time
11 s

TV damper.

Section 2

Beam Power

X-ray radiationInterelectrode capacitances
Plate resistance
6200 Ω
Transconductance
0.0088 S
Amplification factor
4.2
Max plate voltage
500 V
Max screen voltage
150 V
Max plate dissipation
10 W
Max screen dissipation
3.5 W
Max cathode current
230 mA
Rectifier max heater-cathode voltage
200 V

Horizontal deflection; pulse plate 5000 V.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Diode

Characteristic

  • Tube Voltage Drop

    16 V

    Ib=350mA

SECTION 2

Beam Power

Other

  • Peak Positive Pulse Plate Voltage

    5000 V

    HorizontalDeflection

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Diode

Characteristic

  • Tube Voltage Drop for plate current of

    350 mA

    Tube Voltage Drop for plate current of 350 mA 21 volts

  • Heater Voltage (ac/dc) 37.8

    53.2 V

    Heater Voltage (ac/dc) 37.8 53.2 volts

  • Heater Current 0.45

    315 mA

    Heater Current 0.45 0.315 ampere

  • Heater Warm-up Time (Average) 11

    11 s

    Heater Warm-up Time (Average) 11 11 seconds

  • Plate Voltage 130 3500 50

    130 V

    Plate Voltage 130 3500 50 130 volts

  • Grid-No.2 (Screen-Grid) Voltage 130 130 130

    130 V

    Grid-No.2 (Screen-Grid) Voltage 130 130 130 130 volts

  • Grid-No.l (Control-Grid) Voltage —22 0 —

    22 V

    Grid-No.l (Control-Grid) Voltage —22 0 —22 volts

  • Plate Current 450

    60 mA

    Plate Current 450 60 mA

  • Grid-No.2 Current 40

    2.8 mA

    Grid-No.2 Current 40 2.8 mA

  • current of

    1 mA

    current of 1 mA -66 —39 volts

  • Tube voltage drop

    21 V

    Published instantaneous characteristic

Other

  • Plate Voltage

    500 V

    Plate Voltage 500 volts

  • Peak Positive-Pulse Plate Voltage

    5000 V

    Peak Positive-Pulse Plate Voltage 5000 volts

  • Peak Negative-Pulse Plate Voltage

    0 V

    Peak Negative-Pulse Plate Voltage 0 volts

  • Grid-No.2 Voltage

    150 V

    Grid-No.2 Voltage 150 volts

  • DC Grid-No.l Voltage, Negative-bias value

    55 V

    DC Grid-No.l Voltage, Negative-bias value 55 volts

  • Peak Neirative-Pulse Grid-No.l Voltage

    330 V

    Peak Neirative-Pulse Grid-No.l Voltage 330 volts

  • Average Cathode Current

    230 mA

    Average Cathode Current 230 mA

  • Grid-No.l-Circuit Resistance

    1 Mohm

    Grid-No.l-Circuit Resistance 1 megohm

  • Peak Inverse Plate Voltage#

    4200 V

    Peak Inverse Plate Voltage# 4200 volts

  • Peak Plate Current

    1200 mA

    Peak Plate Current 1200 mA

  • Average Plate Current

    200 mA

    Average Plate Current 200 mA

  • Tube Voltage Drop for plate current of

    350 mA

    Tube Voltage Drop for plate current of 350 mA 16 volts

  • Peak inverse plate voltage

    4200 V

    Published rectifier rating

  • Average output/plate current

    200 mA

    Published rectifier operating/rating value

SECTION 2

Beam Power

Characteristic

  • Plate Resistance

    6200 ohm

    Plate Resistance 6200 ohms

  • Amplification factor

    4.2

    Published section characteristic

Other

  • Maximum plate voltage

    130 V

    Published maximum rating

  • Maximum screen-grid voltage

    130 V

    Published maximum rating