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
3BGP7
Three-inch direct-view oscilloscope CRT with electrostatic focusing and deflection. Its P7 blue-white/yellow, long persistence screen and published deflection characteristics support compact precision oscillographic instrumentation.
Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
- Sections
- 1
- Base
- -
- Socket code
- B12A
- Base pins
- -
- Nominal heater
- 1.5 V / 140 mA
Description
Sylvania 3BGP7 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
- 2750 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
1.5 V
Heater Current
140 mA
FocusingMethod
Electrostatic
DeflectionMethod
Electrostatic
Phosphor
P7 blue-white/yellow, long persistence
MinimumUsefulScreen
2.25 x 1.125 in
GridToAllCapacitance
4.5 pF
BetweenDeflectionPlates1_2Capacitance
2 pF
BetweenDeflectionPlates3_4Capacitance
2.5 pF
P1LightOutputMinimum
20 ft-L
P1 variant/reference condition
LineWidthMaximum
0.65 mm
Other
Anode2VoltageMaximum
2750 V
Anode1FocusVoltageMaximum
1100 V
GridNegativeBiasMagnitudeMaximum
200 V
GridPositivePeakVoltageMaximum
2 V
PeakHeaterCathodeVoltageNegative
140 V
PeakVoltageAnode2ToDeflectionPlate
550 V
Anode2Voltage
2000 V
Anode1VoltageForFocus
400-700 V
GridVoltageForCutoff
-38 to -67.5 V
DeflectionFactorPlates1_2
68-92 V/in
DeflectionFactorPlates3_4
28-38 V/in
GridCircuitResistanceMaximum
1.5 Mohm
DeflectionCircuitResistanceMaximum
1 Mohm
Anode2PowerInputMaximum
6 W
AltitudeMaximum
35000 ft