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Specialized - Ballast ·Ballast

K49CB

Battery-equipment ballast regulator designed to stabilize filament current in low-voltage receiver circuits and protect series-connected valve filaments from supply variation.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
-

Description

K49CB is a Raytheon resistance/ballast tube for AC-DC receiver filament strings with a pilot-lamp ballast tap.

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
-
Nominal heater current
-
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

1 physical section, each with unique specifications.

Section 1

Ballast

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Ballast/resistance-tube voltage-drop and pilot-lamp tap ratings captured in parameters.

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

1937 Raytheon Radio Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Ballast

Characteristic

  • Voltage drop

    49 V

    At 300 mA

  • Operating current

    300 mA

    FilamentString

  • Pilot lamp voltage

    10 V

    Two 6.3 V 150 mA lamps in series

  • Pilot lamp voltage

    6.8 V

    One 6.3 V 200 mA lamp

  • Pilot lamp voltage

    4.8 V

    One 6.3 V 250 mA lamp