X79

Radio receiver frequency changer designed for superheterodyne mixer and oscillator service. Its multi-grid construction performs signal conversion, often integrating local oscillation and mixing within one valve.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / -

Description

Miniature triode-hexode frequency changer for operation to 100 MHz.

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: 9
Nominal heater voltage: 6.3 V
Nominal heater current: -
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

Triode

X-ray radiationInterelectrode capacitances

Max plate voltage: 250 V

Section 2

Hexode

X-ray radiationInterelectrode capacitances

Max plate voltage: 250 V
Max screen voltage: 100 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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Application

Oscillator section function
Local oscillator

Other

Oscillator anode voltage
250 V

SECTION 2

Hexode

Construction

Mixer section identity
Hexode

Other

Mixer anode voltage
250 V
Mixer screen voltage
100 V

Application

Frequency-changer service
Explicit

Characteristic

Maximum operating frequency
100 MHz