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
HF amplification
Voltage Pentode - Sharp Cutoff (single) ·Pentode
EF91
Miniature sharp-cutoff RF pentode with high mutual conductance. Mullard and Philips documentation identify it for fixed-gain high-frequency amplification requiring substantial transconductance from a compact tube.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- B7G
- Socket code
- B7G
- Base pins
- 7
- Nominal heater
- 6.3 V / 300 mA
Description
Miniature sharp-cutoff RF pentode with high mutual conductance. Published heater, characteristics, ratings and application information were read from the supplied Mullard sheet.
Socket description
Miniature 7-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- B7G
- Socket code
- B7G
- Base pins
- 7
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 300 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
B7G - 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
- 500000 Ω
- Transconductance
- 0.0076 S
- Max plate voltage
- 300 V
- Max screen voltage
- 300 V
- Max plate dissipation
- 2.5 W
- Max screen dissipation
- 0.65 W
- Max cathode current
- 15 mA
Published maximum ratings, characteristics and operating conditions 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 02
1963 Mullard
Published operating points and test conditions from this source.
SECTION 1
Pentode
Capacitance
Input capacitance
7 pF
Output capacitance
2 pF
Other
Anode current
10 mA
Va=250V; Vg2=250V
Screen current
2.55 mA
Va=250V; Vg2=250V
Characteristic
Equivalent noise resistance
1200 ohm
Input damping
5000 ohm
40 Mc/s
Data set 03
1963 Philips Electron Tubes Handbook V1a
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
Heater voltage
6.3 V
Published heater rating
Heater current
300 mA
Published heater rating
Transconductance
7600 µS
RForIFAmplifier
Other
Plate voltage
250 V
RForIFAmplifier
Screen voltage
250 V
RForIFAmplifier
Plate current
10 mA
RForIFAmplifier
Data set 04
1967 Mullard Receiving and Amplifying Valves
Published operating points and test conditions from this source.
SECTION 1
Pentode
Capacitance
Ci n 7.1
7.1 pF
Published in approved EF91 target datasheet entry; Section1
Cou t 2.1
3.1 pF
Published in approved EF91 target datasheet entry; Section1
Other
P g 2 max
650 mW
Published in approved EF91 target datasheet entry; Section1
II< max
15 mA
Published in approved EF91 target datasheet entry; Section1
Data set 05
1999 Philips E-Z
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
Heater voltage
6.3 V
Heating
Heater current
300 mA
Heating
Maximum plate voltage
300 V
Promoted published datasheet value
Maximum screen voltage
300 V
Promoted published datasheet value
Maximum plate dissipation
2.5 W
Promoted published datasheet value
Capacitance
Capacitances {with external screening) Cg1 =
7.3 pF
Capacitances
Characteristic
v, =
250 V
Published datasheet value
Vg2 =
25 V
Published datasheet value
Vg1 = ~
2 V
Published datasheet value
Ig2 =
2.55 mA
Published datasheet value
Published electrical value
7.65 mA/V
Published datasheet value