1LA6

Low-consumption battery heptode for oscillator-converter service in portable superheterodyne radios. Its economical filament and high plate resistance provide useful frequency conversion from modest receiver supply voltages.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: 7AK
Socket code: B8G
Base pins: 8
Nominal heater: 1.4 V / 50 mA

Description

1LA6 is listed as a pentagrid converter in the supplied receiving-tube handbook. It uses a 1.4 V, 0.05 A directly heated filament. The handbook publishes maximum ratings and representative operating characteristics for its intended service.

Socket description

Loctal 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 7AK
Socket code: B8G
Base pins: 8
Nominal heater voltage: 1.4 V
Nominal heater current: 50 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

7AK - 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: 700000 Ω
Transconductance: 0.00025 S
Max plate voltage: 90 V
Max screen voltage: 65 V
Max cathode current: 3 mA

Pentagrid converter; oscillator characteristics preserved as parameters.

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

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Maximum plate voltage
110 V
Published handbook rating
Maximum screen voltage
65 V
Published handbook rating
Plate voltage
90 V
ClassA
Screen voltage
45 V
ClassA
Control-grid voltage
0 V
ClassA
Plate current
0.55 mA
ClassA
Screen current
0.6 mA
ClassA

Characteristic

Plate resistance
750000 ohm
Published handbook characteristic
Transconductance
250 µS
Published handbook characteristic
Filament voltage
1.4 V
DirectlyHeated DC filament
Filament current
50 mA
DirectlyHeated DC filament

Data set 02

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristic

Conversion Transconductance
250 uS
Converter
Oscillator Transconductance
550 uS
Oscillator;NotOscillating
Oscillator Amplification Factor
40
Oscillator;NotOscillating