Data set 01
1950 Sylvania
Published operating points and test conditions from this source.
SECTION 1
Cathode Ray
Characteristics
Focusing method
Electrostatic
Deflection method
Electrostatic
Phosphor
P7
Specialized - Cathode Ray ·CathodeRay
3BMP7
Three-inch direct-view oscilloscope CRT with electrostatic focusing and deflection and high-voltage accelerating operation. Its P7 blue-white/yellow, long persistence screen provides the persistence characteristics needed for oscillographic instrumentation.
Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
- Sections
- 1
- Base
- -
- Socket code
- B12A
- Base pins
- -
- Nominal heater
- 1.5 V / 140 mA
Description
Sylvania 3BMP7 direct-view oscilloscope CRT with electrostatic focus/deflection; P7 blue-white/yellow, long persistence. Published maximum ratings, capacitances, and typical operating conditions were extracted from the supplied datasheet.
Socket description
Duodecal 12-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- B12A
- Base pins
- -
- Nominal heater voltage
- 1.5 V
- Nominal heater current
- 140 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
1 physical section, each with unique specifications.
Section 1
Cathode Ray
X-ray radiationInterelectrode capacitances
- Max plate voltage
- 6600 V
Published source values promoted where applicable; additional values 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.
Data set 02
1965 Sylvania Electronic Tubes Vol3
Published operating points and test conditions from this source.
SECTION 1
Cathode Ray
Characteristic
Heater Voltage
6.3 V
Heater Current
600 mA
FocusingMethod
Electrostatic
DeflectionMethod
Electrostatic
Phosphor
P7 blue-white/yellow, long persistence
MinimumUsefulScreen
2.68 in
DeflectionFactorUniformityMaximum
2 %
PatternDistortionMaximum
2 %
ModulationMaximum
38 V
Anode3Current=25uA
LineWidthMaximum
0.016 in
Anode3Current=25uA
Other
Anode3VoltageMaximum
6600 V
Anode2VoltageMaximum
2200 V
Anode1FocusVoltageMaximum
1500 V
GridNegativeBiasMagnitudeMaximum
200 V
GridPositivePeakVoltageMaximum
0 V
PeakHeaterCathodeVoltageNegative
50 V
PeakVoltageAnode2ToDeflectionPlate
550 V
Anode3Voltage
4000 V
Anode2Voltage
2000 V
Anode1VoltageForFocus
375-575 V
GridVoltageForCutoff
-45 to -75 V
DeflectionFactorPlates1_2
180-220 V/in
DeflectionFactorPlates3_4
133-163 V/in
GridCircuitResistanceMaximum
1.5 Mohm
DeflectionCircuitResistanceMaximum
5 Mohm
Anode3ToAnode2VoltageRatioMaximum
3
Anode2PowerInputMaximum
6 W
Except3BMP12AverageRatingNote