50A5

50-volt-heater beam tetrode designed for receiver audio-output service, with published output around 4 watts from a compact power stage.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: 6AA
Socket code: IO
Base pins: 6
Nominal heater: 50 V / 150 mA

Description

The BRIMAR 50A5 is a 50 V heater output beam tetrode with about 4.3 W published output.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 6AA
Socket code: IO
Base pins: 6
Nominal heater voltage: 50 V
Nominal heater current: 150 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

6AA - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1Pin 1	—	H — Heater	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN2Pin 2	A	P — Plate (Anode)	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN3Pin 3	A	G2 — Screen Grid	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN4Pin 4	—	NC	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN5Pin 5	—	NC	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN6Pin 6	A	G1 — Control Grid	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN7Pin 7	A	BP — Beam-Forming PlateGroup AA7	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN7Pin 7	A	K — CathodeGroup AA7	Verified 7C5 JEDEC registration, 6AA pin assignment
PIN8Pin 8	—	H — Heater	Verified 7C5 JEDEC registration, 6AA pin assignment

Section ratings

1 physical section, each with unique specifications.

Section 1

Beam Power

X-ray radiationInterelectrode capacitances

Plate resistance: 28000 Ω
Transconductance: 0.008 S
Max plate voltage: 117 V
Max screen voltage: 117 V
Max plate dissipation: 7 W
Max screen dissipation: 1.4 W

Published maximum ratings, operating characteristics, rectifier/deflection data reviewed.

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

1958 Brimar Radio Valve No 7

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Characteristics

Anode Voltage
200 V
Anode Current
50 mA
Screen Voltage
110 V
Screen Current
1.5 mA
Control Grid Voltage
-8 V
Optimum Load
3000 ohm

Other

Power Output
4.3 W
ClassA

Data set 02

195X General Electric Essential Characteristics

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

Maximum plate voltage
200 V
Published handbook rating
Maximum screen voltage
125 V
Published handbook rating
Plate voltage
200 V
ClassA
Screen voltage
125 V
ClassA
Control-grid bias
46 V
ClassA
Plate current
28 mA
ClassA
Screen current
2.2 mA
ClassA
Load resistance
4000 ohm
ClassA
Power output
3.8 W
ClassA

Characteristic

Plate resistance
28000 ohm
Published handbook characteristic
Transconductance
8000 µS
Published handbook characteristic
Heater/filament voltage
50 V
Published heater/filament rating
Heater/filament current
150 mA
Published heater/filament rating

Data set 03

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

Power Output
2 W
ClassA
Similar Type Reference
50L6GT