Data set 01
1960 CBS Hytron
Published operating points and test conditions from this source.
SECTION 1
Beam Power
Other
Pulse Power
20000 W
PulseModulator
Power - Beam (NOT sweep) ·BeamPower
3D21B
CBS-Hytron 3D21B high-vacuum blocking-oscillator and pulse-modulator tube with 6.3/12.6 V series-parallel heater, 3500 V plate rating and 7–21 kW typical pulse output.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- -
- Base pins
- 8
- Nominal heater
- 12.6 V / 850 mA
Description
The CBS-Hytron 3D21B is a high-vacuum blocking-oscillator and pulse-modulator tube suitable for pulse power up to about 20 kW.
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- -
- Base pins
- 8
- Nominal heater voltage
- 12.6 V
- Nominal heater current
- 850 mA
- Parallel heater voltage
- 6.3 V
- Parallel heater current
- 1.7 A
- Series capable
- Yes
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
Beam Power
X-ray radiationInterelectrode capacitances
- Transconductance
- 0.00055 S
- Max plate voltage
- 3500 V
- Max screen voltage
- 850 V
- Max plate dissipation
- 15 W
- Max screen dissipation
- 3 W
- Max grid dissipation
- 0.5 W
CBS-Hytron 1957: maximum plate 3500 V (5000 V transient peak), grid2 850 V, grid1 instantaneous -500 to +220 V, plate dissipation 15 W, grid2 dissipation 3 W, grid1 dissipation 0.5 W. At Va 600 V, Vg2 300 V, Vg1 -30 V, Ia 30 mA, Ig2 2.5 mA: gm 550 µmhos = 0.00055 A/V. Peak heater-cathode 150 V; cathode preheat >=30 s. Pulse operation Va 3500/2500/1500 V, Vg2 800 V, Vg1 -150 V, load 450/305/160 Ω, output 21/14/7 kW. Pulse nominal 10 µs and <=12 µs total per 240 µs. Conditional 4500 V DC plate possible with Vg2 <=400 V, resistive load and no transients. Beam construction unverified; existing classification retained.
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.