6DA7

Dual triode intended for television vertical-deflection service, combining oscillator/driver and power-output functions where applicable. Manufacturer data emphasize vertical-sweep operation, pulse-voltage capability, and the stronger section’s current and dissipation requirements.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: 9EF
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / 1 A

Description

The 6DA7 combines a medium-mu vertical oscillator triode with a low-mu, higher-dissipation vertical amplifier triode for television vertical sweep.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: 9EF
Socket code: B9A
Base pins: 9
Nominal heater voltage: 6.3 V
Nominal heater current: 1 A
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

9EF - Terminal pinout

Electrical assignments shared by every tube using this base designation.

Terminal	Section	Connection	Evidence
PIN1Base Pin	B	P — Plate (Anode) Original chart label: 2P; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN3Base Pin	B	G1 — Control Grid Original chart label: 2G1; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN4Base Pin	—	H — Heater Original chart label: H; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN5Base Pin	—	H — Heater Original chart label: H; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN6Base Pin	A	P — Plate (Anode) Original chart label: 1P; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN7Base Pin	A	G1 — Control Grid Original chart label: 1G1; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN8Base Pin	A	K — Cathode Original chart label: 1K; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF
PIN9Base Pin	B	K — Cathode Original chart label: 2K; manufacturer verification pending	Unverified EIA Base Connections, printed page 132, 9EF

Section ratings

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 2400 Ω
Transconductance: 0.0026 S
Amplification factor: 6.3
Max plate voltage: 300 V
Max plate dissipation: 2 W
Max cathode current: 40 mA

Section 1 vertical oscillator; typical values at 250 V plate.

Section 2

Triode

X-ray radiationInterelectrode capacitances

Plate resistance: 1100 Ω
Transconductance: 0.0057 S
Amplification factor: 6.3
Max plate voltage: 500 V
Max plate dissipation: 6 W
Max cathode current: 40 mA

Second dissimilar triode section; published section-specific values should be interpreted with datasheet section headings.

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

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Plate Voltage
150 V
Published operating/characteristic table

Characteristic

Plate Current
40 mA
Published operating/characteristic table
Amplification Factor
6.3
Published operating/characteristic table
Plate Resistance
1100 ohm
Published operating/characteristic table

Data set 02

1966 Tung Sol Electronic Tubes 2 of 4

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

Grid-to-plate capacitance
2.3 pF
Input capacitance
2 pF
Output capacitance
0.415 pF

Other

Plate voltage
250 V
ClassA1
Plate current
9 mA
ClassA1

SECTION 2

Triode

Capacitance

Grid-to-plate capacitance
6.9 pF
Input capacitance
5.5 pF
Output capacitance
0.82 pF

Other

Plate voltage
150 V
ClassA1
Plate current
40 mA
ClassA1