Data set 01
1948 Brimar Radio Valve Manual
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
HeaterOrFilamentVoltage
25 V
HeaterOrFilamentCurrent
150 mA
Voltage - Dual Triode (similar) ·Triode-Triode
25SN7GT
25 V heater version of the familiar medium-mu twin triode, with separate cathodes and characteristics suited to aircraft and AC/DC equipment using series-connected heater supplies.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- -
- Socket code
- IO
- Base pins
- 8
- Nominal heater
- 25 V / 150 mA
Description
Indirectly heated double triode with separate cathodes for aircraft or A.C./D.C. equipment; otherwise electrically identical to 6SN7GT.
Socket description
International Octal
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- IO
- Base pins
- 8
- Nominal heater voltage
- 25 V
- Nominal heater current
- 150 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
2 physical sections, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7700 Ω
- Transconductance
- 0.0026 S
- Amplification factor
- 20
Representative of two identical sections.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7700 Ω
- Transconductance
- 0.0026 S
- Amplification factor
- 20
Second identical physical triode section; added to align rows with SectionCount.
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
1958 Brimar Radio Valve No 7
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Anode Voltage
250 V
Each section
Anode Current
9 mA
Each section
Grid Voltage
-8 V
Each section
Cathode Bias Resistor
1100 ohm
Each section