5608A

Medium-mu twin triode documented with a 2.5-volt, 2-ampere heater, providing two triode sections for general amplifier service where its electrical characteristics are appropriate.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: 7B
Socket code: -
Base pins: 7
Nominal heater: 2.5 V / 2 A

Description

5608A is listed in the supplied receiving-tube handbook as a medium-mu twin triode. The published heater/filament rating is 2.5 V at 2.0 A.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 7B
Socket code: -
Base pins: 7
Nominal heater voltage: 2.5 V
Nominal heater current: 2 A
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

7B - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1H	—	H — Heater EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN22P	B	P — Plate (Anode) EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN32G1	B	G1 — Control Grid EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN4K	A	K — Cathode EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN51G1	A	G1 — Control Grid EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN61P	A	P — Plate (Anode) EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
PIN7H	—	H — Heater EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B
CAP1G4	A	G4 — Fourth Grid EIA transcription; manufacturer verification pending	Unverified EIA Base Connections, printed page 128, 7B

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 13000 Ω
Transconductance: 0.00245 S
Amplification factor: 32
Max plate voltage: 350 V
Max plate dissipation: 5.5 W

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

Section 2

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 13000 Ω
Transconductance: 0.00245 S
Amplification factor: 32
Max plate voltage: 350 V
Max plate dissipation: 5.5 W

Second identical physical triode section; added to align rows with SectionCount.

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

Triode

Other

Maximum plate voltage
350 V
Published handbook rating
Plate voltage
300 V
ClassA
Control-grid bias
6 V
ClassA
Plate current
6 mA
ClassA

Characteristic

Plate resistance
13000 ohm
Published handbook characteristic
Transconductance
2450 µS
Published handbook characteristic
Amplification factor
32
Published handbook characteristic
Heater/filament voltage
2.5 V
Published heater/filament rating
Heater/filament current
2 A
Published heater/filament rating