Data set 01
1961 Tung Sol
Published operating points and test conditions from this source.
SECTION 1
Rectifier
Characteristic
Cathode Heating Time
3 min
Construction
HydrogenFilled
1
Rectifier - Half Wave ·Rectifier
7789
Indirectly heated hydrogen-filled half-wave diode for high-voltage rectifier circuits. Rated for approximately 20 kV peak inverse voltage, 400 mA DC output, and 1.6 A peak current.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- A4-81
- Socket code
- -
- Base pins
- 8
- Nominal heater
- 5 V / 8.5 A
Description
Indirectly heated hydrogen-filled half-wave diode for high-voltage rectifier circuits.
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- A4-81
- Socket code
- -
- Base pins
- 8
- Nominal heater voltage
- 5 V
- Nominal heater current
- 8.5 A
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
A4-81 - 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
Rectifier
X-ray radiationInterelectrode capacitances
- Rectifier peak inverse voltage
- 20000 V
- Rectifier nominal output current
- 400 mA
- Rectifier peak forward current
- 1.6 A
- Rectifier forward voltage drop
- 40 V
Published ratings and characteristics mapped semantically; identical repeated sections compressed.
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
1965 Tung Sol Industrial Tubes
Published operating points and test conditions from this source.
SECTION 1
Rectifier
Other
Heater voltage
5 V
Heater current
8.5 A
Surge cathode current
30 A
0.1 second
Averaging time
15 s
Ambient temperature
-55 to 75 degC