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Power - Tetrode (NOT beam) (over 1000V 100W) ·Tetrode

QBL54000

Directly heated forced-air-cooled transmitting tetrode, QBL5-4000, designed for RF amplification, modulation, and frequency multiplication with multi-kilowatt ratings. Alternate designation of type 7704.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 32.5 A

Description

A directly heated forced-air-cooled transmitting tetrode (QBL5-4000) for RF amplification, modulation and frequency multiplication, with multi-kilowatt ratings. This is the alternate designation for 7704.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
32.5 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

Tetrode

X-ray radiationInterelectrode capacitances
Transconductance
0.011 S
Amplification factor
8.5
Max plate voltage
5500 V
Max screen voltage
800 V
Max plate dissipation
3000 W
Max screen dissipation
100 W
Max grid dissipation
30 W
Max cathode current
1.3 A

Extracted from supplied datasheet.

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

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristics

  • Filament voltage

    6.3 V

  • Filament current

    32.5 A

  • Amplification factor g1-g2

    8.5

  • Transconductance

    11000 uS

    At5kV800V0.6A

  • Plate Voltage

    4 kV

    PublishedLine: Plate Voltage 5 5 4 4 kV

  • Grid #

    120 mA

    PublishedLine: Grid #2 Current 100 100 120 120 mA

  • Plate Dissipation

    1.5 kW

    PublishedLine: Plate Dissipation 1.4 1.6 1.25 1.5 kW

  • Power Qutput

    2.9 kW

    PublishedLine: Power Qutput 4.1 3.9 3.15 2.9 kW

  • Plate Current

    0.9 mA

    PublishedLine: Plate Current 0.9 mA

  • Plate Input Power

    3.6 kW

    PublishedLine: Plate Input Power 3.6 kW

  • Modulation Power

    1.8 kW

    PublishedLine: Modulation Power 1.8 kW

  • Plate Current

    1280 mA

    PublishedLine: Plate Current 8¢ 1300 80 1290 70 1280 mA

  • Power QOutput

    3.3 kW

    PublishedLine: Power QOutput - 4.4 - 3.85 - 3.3 kW

Other

  • Plate voltage maximum

    5.5 kV

    RFClassC

  • Plate dissipation maximum

    3 kW

  • Plate current maximum

    1.3 A

    RFClassB

  • Screen voltage maximum

    800 V

  • Screen dissipation maximum

    100 W

  • Grid dissipation maximum

    30 W

  • Power output

    4.1 kW

    RFClassC75Mc/s

  • Grid No

    0.35 pF

    PublishedLine: Grid No. 1 to plate max. 0.35 pF i 'R

  • Input

    23.5 pF

    PublishedLine: Input 23.5 pF | P

  • Output

    8.4 pF

    PublishedLine: Output 8.4 pF |

  • (connector

    30 Mc/s

    PublishedLine: (connector 40650 may be used ot frequencies below 30 Mc/s only)

  • Frequency

    220 Mc/s

    PublishedLine: Frequency 30 110 220 Mc/s

  • D.C. Plate Input Power

    5.5 kW

    PublishedLine: D.C. Plate Input Power 5.5 kW

  • Plete Dissipation

    3 kW

    PublishedLine: Plete Dissipation 3 kW

  • Plate Yoltage

    3.2 kv

    PublishedLine: Plate Yoltage 4.5 4 3.2 kv

  • Grid #

    80 mA

    PublishedLine: Grid #1 Voltage 80 mA