Data set 01
1960 CBS Hytron
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Peak Pulse Current
2 A
PulseDuration<=10us
Warmup Time
10 s
To 80 percent stabilized plate current
Voltage - Dual Triode (similar) ·Triode-Triode
6955
CBS-Hytron 6955 medium-mu dual triode for high-peak-current blocking oscillators, pulse modulators and multivibrators, with series/parallel heater.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- 9A
- Socket code
- B9A
- Base pins
- 9
- Nominal heater
- 6.3 V / 350 mA
Description
The CBS 6955 is a medium-mu dual triode for square-wave modulators, blocking oscillators, multivibrators, and high-peak-power pulse circuits.
Socket description
Small-button Noval 9-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- 9A
- Socket code
- B9A
- Base pins
- 9
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 350 mA
- Parallel heater voltage
- 6.3 V
- Parallel heater current
- 350 mA
- Series capable
- Yes
9A - Terminal pinout
Electrical assignments shared by every tube using this base designation.
| Terminal | Section | Connection | Evidence |
|---|---|---|---|
| PIN12P | B | P — Plate (Anode) EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN22G1 | B | G1 — Control Grid EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN32K | B | K — Cathode EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN4H | — | H — Heater EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN5H | — | H — Heater EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN61P | A | P — Plate (Anode) EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN71G1 | A | G1 — Control Grid EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN81K | A | K — Cathode EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
| PIN9HCT | — | HCT — Heater Center Tap EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 130, 9A |
Section ratings
2 physical sections, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7000 Ω
- Transconductance
- 0.00235 S
- Amplification factor
- 16.5
- Max plate voltage
- 300 V
- Max plate dissipation
- 2.75 W
- Max cathode current
- 20 mA
CBS-Hytron 6955 pulse-modulator dual triode section 1. Design-center Class A max plate 300 V, dissipation 2.75 W, cathode current 20 mA, fixed bias grid resistor 0.25 MΩ, self-bias 1 MΩ. Typical Va 250 V Vg -8.5 V Ia 11.5 mA, mu 16.5, rp 7000 Ω, gm 0.00235 A/V; alternate Va 100 V Vg 0 V Ia 13 mA, mu 21.3, rp 5800 Ω, gm 0.0035 A/V. Separate PULSE service max plate SUPPLY 400 V, peak plate 1.25 A, peak cathode 2.2 A, peak grid 0.9 A, peak positive grid +200 V, grid dissipation 0.6 W, plate dissipation 1.35 W at duty 0.0035, pulse 1.5 µs, 2300 pps; NOT continuous ratings. Cgp 1.4 pF, input 1.5 pF, output 0.5 pF, interplate 0.8 pF.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7000 Ω
- Transconductance
- 0.00235 S
- Amplification factor
- 16.5
- Max plate voltage
- 300 V
- Max plate dissipation
- 2.75 W
- Max cathode current
- 20 mA
CBS-Hytron 6955 pulse-modulator dual triode section 2. Design-center Class A max plate 300 V, dissipation 2.75 W, cathode current 20 mA, fixed bias grid resistor 0.25 MΩ, self-bias 1 MΩ. Typical Va 250 V Vg -8.5 V Ia 11.5 mA, mu 16.5, rp 7000 Ω, gm 0.00235 A/V; alternate Va 100 V Vg 0 V Ia 13 mA, mu 21.3, rp 5800 Ω, gm 0.0035 A/V. Separate PULSE service max plate SUPPLY 400 V, peak plate 1.25 A, peak cathode 2.2 A, peak grid 0.9 A, peak positive grid +200 V, grid dissipation 0.6 W, plate dissipation 1.35 W at duty 0.0035, pulse 1.5 µs, 2300 pps; NOT continuous ratings. Cgp 1.4 pF, input 1.5 pF, output 0.4 pF, interplate 0.8 pF.
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.