12SN7GT
12SN7GT has no equivalent designation confirmed by the archive. Completed sales put the typical price at $28.00 per tube.
The 12SN7GT is a glass-bulb tube with an octal base (intermediate shell, 8-pin) that combines two medium-mu triodes in one envelope, using a coated unipotential cathode. It is designed for use as a resistance-coupled amplifier and as a combined vertical oscillator and vertical deflection amplifier in television receivers. The tube can be used in any mounting position.
Ratings
The heater requires 12.6 volts at 0.3 ampere AC or DC. Maximum ratings include a plate voltage of 300 volts, a plate dissipation of 3.5 watts per plate (5.0 watts for both plates), an average cathode current of 20 mA, a peak cathode current of 300 mA, and a grid circuit resistance of 2.2 megohms.
Characteristics
In Class A1 amplifier service, the amplification factor is 20. At 250 plate volts and −8.0 grid volts, the plate current is 9.0 mA; at this plate voltage, the plate resistance is approximately 7,700 ohms and the transconductance is 2,600 micromhos. At 90 plate volts and 0 grid volts, the plate current is 10 mA; at this plate voltage, the plate resistance is approximately 6,700 ohms and the transconductance is 3,000 micromhos.
| Measure | Per tube |
|---|---|
| Median | $28.00 |
| Typical range (25th–75th) | $16.00 – $57.49 |
| Most sales (10th–90th) | $3.86 – $190.00 |
| Extremes incl. outliers | $1.73 – $589.85 |
| Completed sales | 29 |
| Brand | Median | Range | Sales |
|---|---|---|---|
| Sylvania | $45.87 | $27.50 – $65.00 | 6 |
| Tung-Sol | $165.00 | $140.00 – $589.85 | 4 |
| GE | $10.87 | $3.86 – $11.58 | 3 |
| Condition | Median | Sales |
|---|---|---|
| NOS | $33.66 | 18 |
| used | $24.00 | 10 |
Per-tube prices from completed sales, 2026-02-03 to 2026-09-04. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 12SN7GT, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Tung-Sol | 12SN7GT | PDF (206 KB) |
Documents held here and used to write this page.
- - | 3" 16 MAX T-9 23 MAX. 3 15 MAX.
1 further designation appears alongside 12SN7GT in the literature but below the evidence threshold used here, so it is not listed as equivalent.