Power - Triode ·Triode
Directly heated low-load-resistance power-amplifier triode retained as a replacement type for older Sparton receivers, intended for receiver audio-output service.
The 182B (also designated as the 182-B and 482B) is a classic power amplifier triode designed for low load impedance power amplification. It was produced primarily as a replacement tube for older SPARTON receivers.
The 182B is constructed with an ST-14 glass envelope (referenced in outline drawing 14-1) and utilizes a Medium 4-pin base (4-D connection layout). For proper operation, the tube must be mounted in a vertical position.
The 4-pin base configuration provides the following electrical connections:
The 182B features a directly heated filament. The filament specifications are as follows:
| Parameter | Value |
|---|---|
| Filament Voltage (AC or DC) | 5.0 V |
| Filament Current | 1.25 A |
The 182B is rated for a maximum plate voltage of 250 V. Under typical Class A amplifier operating conditions, the tube exhibits the following characteristics:
| Parameter | Operating Point A | Operating Point B |
|---|---|---|
| Plate Voltage | 250 V | 250 V |
| Grid Voltage (Negative) | -35 V | -35 V |
| Plate Current | 18 mA | 20 mA |
| Transconductance (Mutual Conductance) | 1,500 µmhos | 2,000 µmhos |
| Amplification Factor (Mu) | 5.0 | 5.0 |
| Internal Resistance | — | 2,500 Ω |
| Load Impedance | — | 4,500 Ω |
| Power Output | — | 1.35 W |
The variation in plate current (18 mA to 20 mA) and transconductance (1,500 µmhos to 2,000 µmhos) represents different documented typical values under a 250 V plate and -35 V grid bias.
The 182B is classified specifically as a power amplifier triode. Its electrical design makes it suitable for low load impedance power amplifiers. Historically, the tube is intended solely as a replacement part for older SPARTON receivers ("anciens récepteurs SPARTON").
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Promoted from printed maximum-rating/characteristic columns; additional published values retained in TUBE_SECTION_PARAMETER.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Plate Resistance
2500 ohm
Transconductance
2000 µS
Amplification Factor
5
Plate Voltage
250 V
Grid Voltage
-35 V
Plate Current
20 mA
Load Impedance
4500 ohm
Power Output
1.35 W
Data set 02
Published operating points and test conditions from this source.
Plate Voltage
250 V
ClassA