Data set 01
1961 Tung Sol
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Plate Voltage
250 V
Characteristic
Plate Current
1.2 mA
Voltage - Dual Triode (similar) ·Triode-Triode
12AX7A
Controlled-warm-up high-mu twin triode for AF preamplifier service, offering approximately 100 amplification factor with manufacturer-specified low equivalent noise and hum voltage.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- 9A
- Socket code
- B9A
- Base pins
- 9
- Nominal heater
- 12.6 V / 150 mA
Description
High-mu twin triode for AF preamplifier service; source also designates ECC83.
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
- 12.6 V
- Nominal heater current
- 150 mA
- Parallel heater voltage
- 6.3 V
- Parallel heater current
- 300 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
- 62500 Ω
- Transconductance
- 0.0016 S
- Amplification factor
- 100
- Max plate voltage
- 330 V
- Max plate dissipation
- 1.2 W
- Max cathode current
- 8 mA
Each identical triode section.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 62500 Ω
- Transconductance
- 0.0016 S
- Amplification factor
- 100
- Max plate voltage
- 330 V
- Max plate dissipation
- 1.2 W
High-mu low-noise triode; promoted 250-V Class A1 characteristics.
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 Westinghouse Data Book
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Heater Voltage
12.6 V
Heater Current
150 mA
Plate Current
0.5 mA
Plate Resistance
80000 ohm
Transconductance
1250 uS
Amplification Factor
100
Grid To Plate Capacitance
1.7 pF
Input Capacitance
1.6 pF
Output Capacitance
0.46 pF
Other
Plate Voltage
100 V
EachUnit
Grid Voltage
-1 V
EachUnit
Data set 03
1966 Tung Sol Electronic Tubes 2 of 4
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Plate voltage
250 V
ClassA;EachSection
Plate current
1.2 mA
ClassA;EachSection
Grid voltage
-2 V
ClassA;EachSection
Heater warm-up time
11 s
BothSections
Equivalent noise and hum voltage average RMS
1.8 uV
SpecifiedTestCircuit
Characteristic
Plate resistance
62500 ohm
ClassA;EachSection
Transconductance
1600 uS
ClassA;EachSection
Amplification factor
100
ClassA;EachSection
Capacitance
Grid-to-plate capacitance
1.7 pF
EachSection
Input capacitance
1.6 pF
EachSection
Output capacitance
1.6 pF
EachSection
Data set 04
1968 General Electric Co
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Plate Voltage
250 V
EachSection
Amplification Factor
100
EachSection
Plate Resistance
62500 ohm
EachSection
Transconductance
1600 uS
EachSection
Data set 05
1968 Mazda Belvu
Published operating points and test conditions from this source.
SECTION 1
Triode
Application
Application
AF_Preamplifier text
Data set 06
1971 RCA HB3 Binder 5 of 7
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Heater voltage series
12.6 V
SeriesHeater
Heater current series
150 mA
SeriesHeater
Heater voltage parallel
6.3 V
ParallelHeater
Heater current parallel
300 mA
ParallelHeater
Plate voltage
100 V
ClassA1;PublishedPoint1
Plate voltage
250 V
ClassA1;PublishedPoint2
Grid voltage
-1 V
ClassA1;PublishedPoint1
Grid voltage
-2 V
ClassA1;PublishedPoint2
Amplification factor
100
ClassA1
Plate resistance
80000 ohm
ClassA1;PublishedPoint1
Plate resistance
62500 ohm
ClassA1;PublishedPoint2
Transconductance
1250 µS
ClassA1;PublishedPoint1
Transconductance
1600 µS
ClassA1;PublishedPoint2
Plate current
0.5 mA
ClassA1;PublishedPoint1
Plate current
1.2 mA
ClassA1;PublishedPoint2
Equivalent noise and hum voltage
1.8 µV
RMS;ReferencedToGrid
Other
Maximum plate voltage
330 V
ClassA1
Maximum plate dissipation
1.2 W
ClassA1
Peak heater-cathode voltage
200 V
Capacitance
Grid-to-plate capacitance
1.7 pF
Grid-to-cathode-and-heater capacitance
1.6 pF
Plate-to-cathode-and-heater capacitance
0.46 pF
SECTION 2
Triode
Characteristics
Heater voltage series
12.6 V
SeriesHeater
Heater current series
150 mA
SeriesHeater
Heater voltage parallel
6.3 V
ParallelHeater
Heater current parallel
300 mA
ParallelHeater
Plate voltage
100 V
ClassA1;PublishedPoint1
Plate voltage
250 V
ClassA1;PublishedPoint2
Grid voltage
-1 V
ClassA1;PublishedPoint1
Grid voltage
-2 V
ClassA1;PublishedPoint2
Amplification factor
100
ClassA1
Plate resistance
80000 ohm
ClassA1;PublishedPoint1
Plate resistance
62500 ohm
ClassA1;PublishedPoint2
Transconductance
1250 µS
ClassA1;PublishedPoint1
Transconductance
1600 µS
ClassA1;PublishedPoint2
Plate current
0.5 mA
ClassA1;PublishedPoint1
Plate current
1.2 mA
ClassA1;PublishedPoint2
Equivalent noise and hum voltage
1.8 µV
RMS;ReferencedToGrid
Other
Maximum plate voltage
330 V
ClassA1
Maximum plate dissipation
1.2 W
ClassA1
Peak heater-cathode voltage
200 V
Capacitance
Grid-to-plate capacitance
1.7 pF
Grid-to-cathode-and-heater capacitance
1.6 pF
Plate-to-cathode-and-heater capacitance
0.34 pF
Data set 07
1975 RCA RC30
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Heater Voltage (ac/dc) 12.6 S
3 V
Published in approved ECC83 target datasheet entry; Section1
Heater Current 0.16
300 mA
Published in approved ECC83 target datasheet entry; Section1
Grid to Plate 1.7
1.7 pF
Published in approved ECC83 target datasheet entry; Section1
Grid to Cathode and Heater 1.6
1.6 pF
Published in approved ECC83 target datasheet entry; Section1
Plate to Cathode and Heater 0.46
0.34 pF
Published in approved ECC83 target datasheet entry; Section1
Plate Voltage
330 V
Published in approved ECC83 target datasheet entry; Section1
Negative-bias value
55 V
Published in approved ECC83 target datasheet entry; Section1
Positive-bias value
0 V
Published in approved ECC83 target datasheet entry; Section1
Plate Dissipation
1.2 W
Published in approved ECC83 target datasheet entry; Section1
connection),
6.3 V
Published in approved ECC83 target datasheet entry; Section1
250 volts dc ; plate load resistor,
100000 Ω
Published in approved ECC83 target datasheet entry; Section1
250 volts dc ; plate load resistor, 100000 ohms ; cathode resistor,
2700 Ω
Published in approved ECC83 target datasheet entry; Section1
100-^F capacitor ; grid resistor,
0 Ω
Published in approved ECC83 target datasheet entry; Section1
Heater Voltage (ac/dc) 12.6
6.3 V
Published in approved ECC83 target datasheet entry; Section1
Heater Current 0.15
300 mA
Published in approved ECC83 target datasheet entry; Section1
Grid to Plate
1.3 pF
Published in approved ECC83 target datasheet entry; Section1
Grid to Cathode and Heater
1.3 pF
Published in approved ECC83 target datasheet entry; Section1
Plate to Cathode and Heater
0.6 pF
Published in approved ECC83 target datasheet entry; Section1
Plate Voltage
300 V
Published in approved ECC83 target datasheet entry; Section1
Negative-bias value
50 V
Published in approved ECC83 target datasheet entry; Section1
Cathode Current
10 mA
Published in approved ECC83 target datasheet entry; Section1
Plate Dissipation
1.5 W
Published in approved ECC83 target datasheet entry; Section1
Plate Voltage
250 V
Published in approved ECC83 target datasheet entry; Section1
Plate Resistance
22800 Ω
Published in approved ECC83 target datasheet entry; Section1
Transconductance
1750 µS
Published in approved ECC83 target datasheet entry; Section1
Characteristic
Plate Current
3 mA
Published in approved ECC83 target datasheet entry; Section1
Grid Voltage (Approx.) for plate current of
10 mA
Published in approved ECC83 target datasheet entry; Section1
Grid Voltage (Approx.) for plate current of 10 mA
11 V
Published in approved ECC83 target datasheet entry; Section1