6BX6
6BX6 is also designated EF80. Completed sales put the typical price at $17.24 per tube.
Description
The 6BX6 is a pentode with a coated unipotential cathode. It has a small button noval 9-pin base. The maximum overall length is 2-5/8 inches, the maximum seated height is 2-3/8 inches, and the maximum diameter is 7/8 inches. The tube can be mounted in any position.
Basing and Ratings
The JETEC basing designation is 9AQ-0-0. Pin connections are as follows: pin 1 cathode; pin 2 grid No. 1; pin 3 cathode; pins 4 and 5 heater; pin 6 internal shield; pin 7 plate; pin 8 grid No. 2; pin 9 grid No. 3. The heater requires 6.3 volts at 300 mA.
Maximum ratings are: plate voltage 250 volts; plate dissipation 2.5 watts; grid No. 2 voltage 250 volts; grid No. 2 dissipation 0.65 watts; cathode current 15 mA.
| Designation | Evidence | Confidence |
|---|---|---|
| EF80 | 77 independent documents | strong |
Equivalence is asserted only where the archive's own literature states it directly, in at least 40 separate documents. Tubes that merely substitute in some circuits are not listed here.
| Measure | Per tube |
|---|---|
| Median | $17.24 |
| Typical range (25th–75th) | $10.19 – $22.84 |
| Most sales (10th–90th) | $6.14 – $79.68 |
| Extremes incl. outliers | $4.98 – $135.32 |
| Completed sales | 18 |
| Condition | Median | Sales |
|---|---|---|
| NOS | $17.06 | 12 |
| used | $28.67 | 3 |
Per-tube prices from completed sales, 2026-07-02 to 2026-09-20. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 6BX6, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Philips | 6BX6 | PDF (159 KB) |
| Tesla | EF80 | PDF (4822 KB) |
| WF | EF80 | PDF (860 KB) |
| Philips | EF80 | PDF (746 KB) |
| Mazda-Belvu | EF80 | PDF (392 KB) |
| La Radiotechnique | EF80 | PDF (101 KB) |
| RFT | EF80 | PDF (100 KB) |
| Philips | EF80 | PDF (94 KB) |
| Brimar | EF80 | PDF (34 KB) |
Documents held here and used to write this page.
- MINISTERSTVO PŘESNÉHO STROJÍRENSTVÍ (filed under EF80)
- 6 BX 6
2 further designations appear alongside 6BX6 in the literature but below the evidence threshold used here, so they are not listed as equivalent.