8890

Beam-power transmitting tube for substantial RF amplifier service, combining high-voltage operation with power-handling capability for professional transmitting equipment.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: B9A
Base pins: -
Nominal heater: 5.7 V / 125 A

Description

The 8890 is a high-power linear beam-power RF/television tube. The supplied datasheet provides heater or filament data, maximum ratings, operating conditions, RF output information, and interelectrode capacitances where applicable.

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: -
Nominal heater voltage: 5.7 V
Nominal heater current: 125 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

Beam Power

X-ray radiationInterelectrode capacitances

Max plate voltage: 8000 V
Max screen voltage: 1650 V
Max plate dissipation: 5000 W
Max screen dissipation: 250 W
Max cathode current: 5 A

Published ratings, characteristics, and operating data promoted 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

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

Maximum DC Plate Voltage
8000 V
Up to 400 MHz
Maximum DC Screen Voltage
1650 V
Up to 400 MHz
Maximum DC Control-Grid Voltage
-450 V
Up to 400 MHz
Maximum DC Plate Current
5 A
Maximum Control-Grid Input
150 W
Maximum Screen Input
250 W
Plate Dissipation
5000 W
Typical Plate Voltage
6500 V
Grid-drive circuit at 108 MHz
Typical Screen Voltage
1000 V
Grid-drive circuit at 108 MHz
Typical Plate Current
2.35 A
Grid-drive circuit at 108 MHz
Driver Power Output
60 W
Grid-drive circuit at 108 MHz
Useful Power Output
10000 W
Grid-drive circuit at 108 MHz
TV Synchronizing-Level Plate Voltage
5030 V
Cathode drive at 216 MHz
TV Synchronizing-Level Useful Power Output
7000 W
Cathode drive at 216 MHz
TV Blanking-Level Useful Power Output
3940 W
Cathode drive at 216 MHz

Characteristics

Mu Factor, Screen to Control Grid
20
Grid-No.1 to Plate Capacitance
0.4 pF
Grid-No.1 to Filament Capacitance
70 pF
Plate to Filament Capacitance
0.05 pF
Grid-No.1 to Screen Capacitance
95 pF
Screen to Plate Capacitance
12 pF
Screen to Filament Capacitance
2.5 pF
Minimum Heating Time
15 s