Data set 01
1951 Mullard Valve and Service Manual
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristics
Cutoff characteristic
Sharp cutoff
Application
Application
Short-wave RF amplification
Voltage Pentode ·Pentode
EF50
Mullard high-slope RF pentode for demanding radio, radar, television, and wideband signal-amplifier applications.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- B9G
- Socket code
- B9G
- Base pins
- 9
- Nominal heater
- 6.3 V / 300 mA
Description
The Mullard EF50 is a single-ended RF pentode with dual control-grid operating modes.
Socket description
Loctal 9-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- B9G
- Socket code
- B9G
- Base pins
- 9
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 300 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
B9G - Terminal pinout
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
Section ratings
1 physical section, each with unique specifications.
Section 1
Pentode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 1000000 Ω
- Transconductance
- 0.0065 S
- Max plate voltage
- 300 V
- Max screen voltage
- 300 V
- Max plate dissipation
- 3 W
- Max screen dissipation
- 1.7 W
- Max cathode current
- 15 mA
Published ratings and characteristics promoted from the supplied Brimar 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 02
1958 Mullard Receiving Tubes
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
Heater Voltage
6.3 V
Heater Current
300 mA
Data set 03
1963 Mullard
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristics
Heater Voltage
6.3 V
Heater Current
300 mA
Plate Voltage
250 V
Screen Voltage
250 V
Plate Current
10 mA
Screen Current
3 mA
Transconductance
6500 uS
Plate Resistance
1000000 ohm
Plate-Grid Capacitance Maximum
0.007 pF
Input Capacitance Average
8.3 pF
Output Capacitance Average
5.2 pF
Grid1-Grid2 Capacitance
2.4 pF
Input Damping Resistance
4000 ohm
50MHz
Output Damping Resistance
50000 ohm
50MHz
Grid Voltage for 10:1 Transconductance Reduction
-4.5 V
ControlledByGrid1
Grid Voltage for 10:1 Transconductance Reduction
-53 V
ControlledByGrid3
Other
Maximum Plate Voltage
300 V
Maximum Screen Voltage
300 V
Maximum Plate Dissipation
3 W
Maximum Screen Dissipation
1.7 W
Data set 04
1999 Philips E-Z
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristics
Heater voltage
6.3 V
Heater current
300 mA
Typical plate voltage
250 V
Typical screen voltage
250 V
Typical grid voltage
-1.55 V
Typical plate current
10 mA
Typical screen current
3 mA
Transconductance
6500 uS
Plate resistance
1 Mohm
Capacitance
Plate capacitance
5.2 pF
Grid input capacitance
8.3 pF
Plate-grid capacitance maximum
0.007 pF
Grid-cathode capacitance maximum
0.01 pF