6FQ7
6FQ7 has no equivalent designation confirmed by the archive. Completed sales put the typical price at $16.75 per tube.
The 6FQ7 is a general-purpose, medium-mu twin triode of the 9-pin miniature type. It is intended particularly for use as a vertical-deflection oscillator or horizontal-deflection oscillator in television receivers.
Construction
The 6FQ7 uses an EIA 9LP base, with a small button 9-pin E9-1 base and a T-6 1/2 glass envelope. Its maximum diameter is 1 1/8 inches, and its maximum over-all length and seated height are both 2 3/8 inches.
Ratings
The heater is rated at 6.3 volts for parallel operation, with a current of 0.6 amperes and a warm-up time of 11 seconds. For each section, the maximum plate dissipation is 4.0 watts. In horizontal-deflection oscillator service, the maximum DC plate voltage is 330 volts and the peak negative-pulse grid voltage rating is 660 volts; in vertical-deflection oscillator service, the peak negative-pulse grid voltage rating is 440 volts.
Characteristics
At a plate voltage of 250 volts and a grid voltage of -8.0 volts, each section exhibits an amplification factor of 20, a plate resistance of approximately 7700 ohms, a transconductance of 2600 micromhos, and a plate current of 9.0 milliamperes. Interelectrode capacitances for section 1 are 3.6 pf grid-to-plate, 2.4 pf input, and 0.34 pf output; for section 2, they are 3.8 pf grid-to-plate, 2.4 pf input, and 0.26 pf output. The plate-to-plate capacitance is 1.0 pf.
Base Connections
Pin 1 is the plate of section 2, pin 2 is the grid of section 2, pin 3 is the cathode of section 2, pin 4 is the heater, pin 5 is the heater, pin 6 is the plate of section 1, pin 7 is the grid of section 1, pin 8 is the cathode of section 1, and pin 9 has no connection.
| Measure | Per tube |
|---|---|
| Median | $16.75 |
| Typical range (25th–75th) | $11.50 – $22.50 |
| Most sales (10th–90th) | $7.54 – $28.98 |
| Extremes incl. outliers | $2.95 – $63.29 |
| Completed sales | 31 |
| Brand | Median | Range | Sales |
|---|---|---|---|
| RCA | $17.24 | $13.95 – $19.95 | 14 |
| GE | $14.32 | $8.99 – $26.07 | 6 |
| Condition | Median | Sales |
|---|---|---|
| NOS | $16.98 | 16 |
| used | $12.26 | 10 |
Per-tube prices from completed sales, 2026-02-24 to 2026-09-23. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 6FQ7, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| General Electric | 6FQ7 | PDF (440 KB) |
| Ei | 6FQ7 | PDF (310 KB) |
| RCA (HB3) | 6FQ7 | PDF (207 KB) |
| RCA (RC30) | 6FQ7 | PDF (129 KB) |
| Tung-Sol | 6FQ7 | PDF (105 KB) |
Documents held here and used to write this page.
- 6FQ7