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Voltage - Triode (under 100V) ·Triode-Triode

6N21B

Russian double triode designed for low-frequency voltage amplification, providing two triode sections for compact small-signal amplifier circuits.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
-
Base pins
-
Nominal heater
6.3 V / 395 mA

Description

The 6H21B double triode is designed for ampli- JICHHMS HalpsAXKeHHs HH3KOH YaCTOTHI fication of low-frequency voltage.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
395 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
Transconductance
0.038 S
Amplification factor
82
Max plate voltage
57 V
Max plate dissipation
1 W
Max cathode current
10 mA

Bilingual Russian/English datasheet; English text used as primary extraction source.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.038 S
Amplification factor
82
Max plate voltage
57 V
Max plate dissipation
1 W
Max cathode current
10 mA

Second physical triode restored.

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 01

195X Russian

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage

    6.3 V

    Published nominal heater condition.

  • Heater current

    395 mA

    Published heater current.

  • Transconductance

    3500 µS

    Published characteristic; normalized to µS.

  • Amplification factor

    82

    Published characteristic.

Other

  • Maximum plate voltage

    250 V

    Published limiting operating value.

  • Maximum plate dissipation

    1 W

    Published limiting operating value.

Data set 02

1970 Russian Tubes Mashpriborintorg

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • U

    63 V

    Published datasheet line: U, 63V ) 35x13mA

  • I

    395+35 mA

    Published datasheet line: I, 395+35 mA S1) 38+12mA/V

  • U

    200 V

    Published datasheet line: U, 200V ply 82X

  • R

    330 Q

    Published datasheet line: R} 330Q

  • pF Cin

    < 13 pF

    Published datasheet line: pF Cin < 13 pF

  • Cnx

    1,65+0,35 pF

    Published datasheet line: Cnx 1,65+0,35 pF Cala2 < 0,045 pF

  • Uy

    7 V

    Published datasheet line: Uy 7V 57V I 10 mA

  • U

    250 V

    Published datasheet line: U, 250 V U 200 V

  • U

    350 V

    Published datasheet line: U, 350V Ryr?) 2MQ

  • UgT

    —50 V

    Published datasheet line: UgT —50V Thationa ggge ¢

  • P

    1 W

    Published datasheet line: P, 1 W

Other

  • Uy

    7 V

    Published datasheet line: Uy 7V 57V I 10 mA

  • U

    250 V

    Published datasheet line: U, 250 V U 200 V

  • U

    350 V

    Published datasheet line: U, 350V Ryr?) 2MQ

  • UgT

    —50 V

    Published datasheet line: UgT —50V Thationa ggge ¢

  • P

    1 W

    Published datasheet line: P, 1 W

  • PublishedValue

    7 g

    Published datasheet line: ] 7/[ JS_ g 5 J_fifi »

  • A b_ q / // . F E- Wl

    74 A

    Published datasheet line: & ’ A b_% q,*/— // . F~ E-?Wl” 74

  • A A

    5 A

    Published datasheet line: A A ‘ 5 -

Data set 03

1981 Russian Tubes Katsnelson and Larionov

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater voltage

    6.3 V

    Published nominal heater condition.

  • Heater current

    395 mA

    Published heater current.

  • Plate current

    3.5 mA

    Published basic-parameter operating point.

  • Transconductance

    3800 µS

    Published basic-parameter value; normalized to µS.

  • Amplification factor

    82

    Published basic-parameter value.

  • Service life

    2000 h

    Published service-life figure.

Other

  • Maximum plate voltage

    252 V

    Published limiting operating value.

  • Maximum cathode current

    10 mA

    Published limiting cathode-current value.

  • Maximum plate dissipation

    1 W

    Published per-triode plate dissipation.