DF22

Variable-mu pentode designed for high-frequency and intermediate-frequency amplification. Philips documentation provides filament data, ratings, characteristics, capacitances, and operating conditions for controlled-gain receiver service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: OCTAL
Socket code: IO
Base pins: 8
Nominal heater: 1.4 V / 50 mA

Description

Variable-mu pentode for H.F. and I.F. amplification. The supplied Philips sheet was read for heater/filament data, ratings, characteristics, capacitances, and operating conditions where published.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: OCTAL
Socket code: IO
Base pins: 8
Nominal heater voltage: 1.4 V
Nominal heater current: 50 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: Yes

OCTAL - 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: 2500000 Ω
Transconductance: 0.0011 S
Max plate voltage: 135 V
Max screen voltage: 135 V
Max plate dissipation: 0.2 W
Max screen dissipation: 0.1 W
Max cathode current: 3 mA

Variable-mu RF/IF pentode; uncontrolled characteristic promoted.

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

1999 Philips 0-D

Published operating points and test conditions from this source.

SECTION 1

Pentode

Capacitance

Output capacitance
6.8 pF
Input capacitance
5 pF
Plate-grid capacitance maximum
0.005 pF

Characteristics

Plate voltage
120 V
Grid bias
-1.5 V
Uncontrolled
Plate current
1.4 mA
Screen current
0.3 mA
Transconductance
1100 uS
Plate resistance
2.5 Mohm
Screen-grid amplification factor
25