1R5WA

Ruggedized low-power heptode converter for oscillator and mixer service in portable or specialized receiving equipment. Low filament demand and strengthened construction suit demanding battery-powered applications.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: 7AT
Socket code: B7G
Base pins: 7
Nominal heater: 1.25 V / 50 mA

Description

Ruggedized filament-type heptode converter for battery-operated equipment and military portable service.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 7AT
Socket code: B7G
Base pins: 7
Nominal heater voltage: 1.25 V
Nominal heater current: 50 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

7AT - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1G5	A	G5 — Fifth GridGroup 7AT1 Original EIA source label G5; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN1F	—	F — FilamentGroup 7AT1 Original EIA source label F; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN2P	A	P — Plate (Anode) Original EIA source label P; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN3G2	A	G2 — Screen GridGroup 7AT3 Original EIA source label G2; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN3G4	A	G4 — Fourth GridGroup 7AT3 Original EIA source label G4; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN4G1	A	G1 — Control Grid Original EIA source label G1; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN5G5	A	G5 — Fifth GridGroup 7AT5 Original EIA source label G5; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN5F	—	F — FilamentGroup 7AT5 Original EIA source label F; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN6G3	A	G3 — Suppressor Grid Original EIA source label G3; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT
PIN7F	—	F — Filament Original EIA source label F; manufacturer confirmation pending	Unverified EIA Base Connections, printed page 128, 7AT

Section ratings

1 physical section, each with unique specifications.

Section 1

Heptode

X-ray radiationInterelectrode capacitances

Transconductance: 0.000235 S
Max plate voltage: 100 V
Max screen voltage: 75 V
Max plate dissipation: 0.1 W
Max screen dissipation: 0.019 W
Max cathode current: 6.5 mA

Published maximum ratings and characteristics promoted from approved source.

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

1938 Raytheon

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

HeaterVoltageNominal
1.25 V
Nominal
HeaterCurrentNominal
50 mA
Nominal
Maximum Plate Voltage
90 V
Maximum Screen Voltage
90 V
Maximum Plate Dissipation
0.1 W
Maximum Cathode Current
2.5 mA

Characteristic

Transconductance
235 µS
Typical

Data set 02

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

MaximumImpactAcceleration
450 G
ShockTest
MaximumVibrationalAcceleration
2.5 G
96HourFatigueTest

Data set 03

1966 Tung Sol Electronic Tubes 3 of 4

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Maximum impact acceleration
450 G
Ruggedized
Maximum vibrational acceleration
2.5 G
Ruggedized
Nominal filament voltage
1.25 V
Filament current
50 mA
Plate voltage
90 V
Typical
Grid #2 voltage
45 V
Typical
Plate current
0.9 mA
Typical

Characteristic

Cathode current
6.5 mA