Data set 01
1950 Sylvania
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Heater Current
90 mA
Nominal published value
Voltage - Dual Triode (similar) ·Triode-Triode
7887
Premium subminiature medium-mu dual triode with separate cathodes for oscillator, amplifier, and low-power servo circuits, designed for high reliability in severe environments.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- 8DG
- Socket code
- B8D
- Base pins
- 8
- Nominal heater
- 26.5 V / 90 mA
Description
A premium subminiature medium-mu dual triode with separate cathodes for oscillator, amplifier and low-power servo circuits, designed for severe environments and high reliability.
Socket description
Subminiature 8-lead
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- 8DG
- Socket code
- B8D
- Base pins
- 8
- Nominal heater voltage
- 26.5 V
- Nominal heater current
- 90 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
8DG - Terminal pinout
Electrical assignments shared by every tube using this base designation.
| Terminal | Section | Connection | Evidence |
|---|---|---|---|
| PIN12P | B | P — Plate (Anode) EIA source transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN22G1 | B | G1 — Control Grid Original EIA label 2G1; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN3H | — | H — Heater Original EIA label H; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN42K | B | K — Cathode Original EIA label 2K; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN51K | A | K — Cathode Original EIA label 1K; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN6H | — | H — Heater Original EIA label H; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN71G1 | A | G1 — Control Grid Original EIA label 1G1; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
| PIN81P | A | P — Plate (Anode) Original EIA label 1P; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 8DG |
Section ratings
2 physical sections, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Transconductance
- 0.005 S
- Amplification factor
- 20
- Max plate voltage
- 165 V
- Max plate dissipation
- 1.1 W
Primary physical section. Sylvania 7887: maximum DC plate voltage 165 V; peak forward plate voltage 330 V. Plate dissipation 1.1 W; published typical transconductance 5000 µmhos and amplification factor 20 at 100 V plate voltage, 220 Ω cathode resistor.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Transconductance
- 0.005 S
- Amplification factor
- 20
- Max plate voltage
- 165 V
- Max plate dissipation
- 1.1 W
Second physical section. Sylvania 7887: maximum DC plate voltage 165 V; peak forward plate voltage 330 V. Plate dissipation 1.1 W; published typical transconductance 5000 µmhos and amplification factor 20 at 100 V plate voltage, 220 Ω cathode resistor.
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.