Skip to main content
Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

Power - Pentode (NOT beam) ·Diode-Diode-Pentode

CBL1

Combined tube containing an output pentode and two detector diodes for AC/DC receiver service. It integrates radio detection and control functions with several watts of audio power output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
3
Base
-
Socket code
-
Base pins
-
Nominal heater
44 V / 200 mA

Description

Combined valve containing an output pentode and two detector diodes, intended for AC/DC receiver service and capable of several watts of audio output under the published operating conditions.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
44 V
Nominal heater current
200 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

3 physical sections, each with unique specifications.

Section 1

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
200 V
Max cathode current
0.8 mA
Rectifier peak inverse voltage
200 V
Rectifier nominal output current
0.8 mA

Published operating point, characteristic values and capacitance column reviewed.

Section 2

Diode

X-ray radiationInterelectrode capacitances
Max plate voltage
200 V
Max cathode current
0.8 mA

Published operating point, characteristic values and capacitance column reviewed.

Section 3

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
35000 Ω
Transconductance
0.008 S
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
9 W
Max screen dissipation
2 W
Max cathode current
70 mA

Published operating point, characteristic values and capacitance column 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 01

1938 Philips Miniwatt Vacuum Tube Catalog

Published operating points and test conditions from this source.

SECTION 3

Pentode

Other

  • Plate voltage

    200 V

    Published table operating point

  • Plate current

    45 mA

    Published table operating point

  • Control-grid bias

    8.5 V

    Published table operating point

  • Screen voltage

    200 V

    Published table operating point

  • Screen current

    6 mA

    Published table operating point

  • Optimum load resistance

    4500 ohm

    Published table operating point

  • Power output

    5 W

    Published table operating point

  • Maximum plate dissipation

    9 W

    Published table rating

Characteristic

  • Transconductance

    8000000 µS

    Published table characteristic

  • Plate resistance

    35000 ohm

    Published table characteristic

  • Heater/filament voltage

    44 V

    Published heater/filament rating

  • Heater/filament current

    200 mA

    Published heater/filament rating

Data set 02

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Diode

Other

  • Diode anode voltage maximum

    200 V

  • Diode anode current maximum

    0.8 mA

  • Diode grid-current test voltage maximum

    -1.3 V

    At Id=+0.3 uA

SECTION 2

Diode

Other

  • Diode anode voltage maximum

    200 V

  • Diode anode current maximum

    0.8 mA

  • Diode grid-current test voltage maximum

    -1.3 V

    At Id=+0.3 uA

SECTION 3

Pentode

Other

  • Anode voltage

    200 V

  • Screen voltage

    200 V

  • Output power

    4 W

  • Anode supply voltage maximum

    400 V

  • Heater-cathode voltage maximum

    125 V