EK90

Radio receiver frequency changer combining oscillator and mixer functions for superheterodyne conversion. Its multi-grid construction translates incoming RF signals to the intermediate frequency within the receiver front end.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: B7G
Socket code: B7G
Base pins: 7
Nominal heater: 6.3 V / 300 mA

Description

Heptode frequency changer intended for mixer and oscillator service. Published heater, characteristics, ratings and application information were read from the supplied Mullard sheet.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: B7G
Socket code: B7G
Base pins: 7
Nominal heater voltage: 6.3 V
Nominal heater current: 300 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

B7G - 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

Heptode

X-ray radiationInterelectrode capacitances

Plate resistance: 1000000 Ω
Transconductance: 0.000475 S
Max plate voltage: 250 V
Max screen voltage: 100 V
Max plate dissipation: 1 W
Max screen dissipation: 1 W
Max cathode current: 14 mA

Published electrical characteristics and ratings 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

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Anode current
10.6 mA
Separate excitation; Va=250V
Screen-grid current
3 mA
Separate excitation; Va=250V

Characteristic

Conversion conductance
475 uS
Separate excitation
Oscillator transconductance
7250 uS
Oscillator section