Data set 01
1931 Cunningham Radio Tubes
Published operating points and test conditions from this source.
SECTION 1
Ballast
Characteristics
Regulator maintaining/rated voltage
90 V
Regulator starting voltage
125 V
Warm-up to final regulation
10 min
Specialized - Ballast ·Ballast
C386
Current-regulating ballast device for receiver heater or filament circuits, using temperature-dependent resistance to hold operating current substantially constant.
Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
- Sections
- 1
- Base
- -
- Socket code
- UX4
- Base pins
- 4
- Nominal heater
- -
Description
C386: Cunningham line-voltage ballast regulator. The complete bulletin was read for construction, ratings, circuit recommendations, and operating characteristics.
Socket description
Medium-shell UX 4-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- UX4
- Base pins
- 4
- 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
- Regulator voltage
- 90 V
- Regulator minimum current
- 10 mA
- Regulator maximum current
- 50 mA
- Regulator starting voltage
- 125 V
- Regulator maintaining voltage
- 90 V
Published ratings and characteristic constants promoted where applicable; operating recommendations retained as 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.