Data set 01
1951 Mullard Valve and Service Manual
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Heater Voltage
6.3 V
Heater Current
400 mA
Voltage - Dual Triode (similar) ·Triode-Triode
ECC33
High-slope, low-impedance double triode explicitly designed for flip-flop, scaling, and computer circuits, providing two similar sections for digital switching and counting applications.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- -
- Socket code
- IO
- Base pins
- 8
- Nominal heater
- 6.3 V / 400 mA
Description
High-slope low-impedance double triode for flip-flop, scaling, and computer circuits.
Socket description
International Octal
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- IO
- Base pins
- 8
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 400 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
Terminal pinout
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
Section ratings
2 physical sections, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 9700 Ω
- Transconductance
- 0.0036 S
- Amplification factor
- 35
- Max plate voltage
- 300 V
- Max plate dissipation
- 2.5 W
- Max cathode current
- 20 mA
Published Mullard ratings and characteristics promoted from the supplied source.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 9700 Ω
- Transconductance
- 0.0036 S
- Amplification factor
- 35
- Max plate voltage
- 300 V
- Max plate dissipation
- 2.5 W
- Max cathode current
- 20 mA
Second 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 02
1963 Mullard
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Plate voltage
250 V
Grid voltage
-4 V
Plate current
9 mA
Transconductance
3.6 mA/V
Amplification factor
35
Other
Plate voltage maximum
300 V
Plate dissipation maximum
2.5 W
Cathode current maximum
20 mA
Capacitance
Inter-section plate capacitance
0.75 pF
Plate-grid capacitance each section
2.5 pF
Grid-cathode capacitance each section
3.5 pF
Application
Application
Flip-flop / scaler / computer circuit
Data set 03
1967 Mullard Receiving Tubes for Maintenance
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
gm
3.6 mA
Published in approved ECC33.pdf target datasheet; Section1
Ik max
20 mA
Published in approved ECC33.pdf target datasheet; Section1