Data set 01
1940 RCA
Published operating points and test conditions from this source.
SECTION 1
Heptode
Application
Application
PentagridConverter text
Voltage Radio Detector Converter ·Heptode
7B8LM
Receiver oscillator-converter combining local oscillation and signal mixing for superheterodyne frequency conversion. Its multi-grid structure integrates the front-end frequency-changing functions in one envelope.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- B8G
- Base pins
- 8
- Nominal heater
- 6.3 V / 300 mA
Description
Pentagrid heptode converter for oscillator and frequency-converter service.
Socket description
Loctal 8-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- B8G
- Base pins
- 8
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 300 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
Heptode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 360000 Ω
- Transconductance
- 0.00055 S
- Max plate voltage
- 250 V
- Max screen voltage
- 100 V
Published ratings and characteristics promoted from the approved RCA source.
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.