Alternatives & variations Download PDF datasheet

8A56HM

Miniaturized eight-inch radar display CRT with low-voltage electrostatic focusing and approximately 43-degree magnetic deflection for compact radar indicators.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized

Sections: 1
Base: B9A
Socket code: -
Base pins: -
Nominal heater: 6.3 V / 300 mA

Description

Miniaturized 8-inch radar display CRT with low-voltage electrostatic focus and 43-degree magnetic deflection.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: B9A
Socket code: -
Base pins: -
Nominal heater voltage: 6.3 V
Nominal heater current: 300 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

B9A - 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

Cathode Ray

X-ray radiationInterelectrode capacitances

Max plate voltage: 15000 V

Promoted fields were populated only where the Ferranti sheet maps cleanly to the locked schema; additional ratings and operating values are retained in TUBE_SECTION_PARAMETER.

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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

First-anode voltage maximum
600 V
Second-and-fourth-anode voltage minimum
8000 V
Third-anode voltage minimum
-500 V
Third-anode voltage maximum
500 V
First-anode voltage
300 V
ValveDrive
Second-and-fourth-anode voltage
12000 V
ValveDrive
Third-anode focus voltage minimum
-300 V
ValveDrive
Third-anode focus voltage maximum
300 V
ValveDrive
Visual cutoff grid voltage
-60 V
ValveDrive