Voltage Pentode - Remote Cutoff (single) ·Pentode
Mullard variable-mu RF pentode designed for controlled RF or IF amplifier service. Its gradual cutoff characteristic supports automatic gain regulation in receiver signal stages.
The Mullard DF33 is a variable-mu RF pentode for controlled RF or IF amplifier service.
International Octal
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Published Mullard/Philips ratings and characteristics promoted where applicable; additional values retained as parameters.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Anode Voltage
90 V
Screen Voltage
90 V
Anode Current
1.2 mA
Screen Current
0.3 mA
Control Grid Voltage for Low Transconductance
-4 V
Transconductance=5uA/V
Data set 02
Published operating points and test conditions from this source.
Cutoff characteristic
Variable-mu
Application
RF / IF amplifier
Data set 03
Published operating points and test conditions from this source.
Filament Voltage
1.4 V
DCOnly
Filament Current
50 mA
DCOnly
Plate Voltage
90 V
Screen Voltage
90 V
Plate Current
1.2 mA
Screen Current
0.3 mA
Plate Resistance
1500000 ohm
Transconductance
750 uS
Grid Voltage for 150:1 Transconductance Reduction
-4 V
Plate-Grid Capacitance
0.007 pF
Maximum
Output Capacitance
9.5 pF
Maximum Plate Voltage
110 V
Maximum Screen Voltage
110 V