12BE6
12BE6 is also designated HK90. Completed sales put the typical price at $11.20 per tube.
The 12BE6 is a pentagrid converter of glass, miniature 7-pin construction, with a coated unipotential cathode, intended for service as a combined oscillator and mixer in superheterodyne receivers.
Construction and Ratings
The 12BE6 uses a miniature button 7CH base and a glass bulb. It can be used in any mounting position. The heater is rated at 12.6±10% volts at 0.15 amp AC or DC. Except for heater ratings, the 12BE6 is identical to the 6BE6.
Maximum Ratings
Maximum plate voltage is 330 volts. Maximum voltage on grids #2 and #4 is 110 volts, with a maximum supply voltage of 330 volts for those grids. Maximum negative DC grid #3 voltage is -55 volts; maximum positive DC grid #3 voltage is 0 volts. Maximum plate dissipation is 1.1 watts, and maximum dissipation for grids #2 and #4 is also 1.1 watts. Maximum cathode current is 15.5 mA. Maximum peak heater-cathode voltage is 200 volts, in either polarity (heater negative or positive with respect to cathode).
Typical Operating Characteristics
At plate voltage 250 V, grid #3 voltage -1.5 V, and grids #2 and #4 voltage 100 V, the datasheet gives a conversion transconductance of 475 µmhos, a plate resistance of approximately 1.0 megohm, and a plate current of 2.9 mA.
| Designation | Evidence | Confidence |
|---|---|---|
| HK90 | 49 independent documents | confirmed |
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 | $11.20 |
| Typical range (25th–75th) | $3.12 – $13.47 |
| Most sales (10th–90th) | $2.25 – $19.40 |
| Extremes incl. outliers | $0.52 – $109.75 |
| Completed sales | 29 |
| Brand | Median | Range | Sales |
|---|---|---|---|
| GE | $13.22 | $13.04 – $21.95 | 5 |
| RCA | $10.09 | $9.47 – $14.40 | 5 |
| Sylvania | $5.00 | $4.95 – $13.47 | 3 |
| Condition | Median | Sales |
|---|---|---|
| NOS | $15.70 | 10 |
| used | $3.24 | 10 |
Per-tube prices from completed sales, 2026-02-22 to 2026-11-01. Matched pairs and quads are divided out. See the price index for how these move over time.
Original manufacturer datasheets for 12BE6, hosted by Frank Philipse's Electron Tube Data sheets.
| Manufacturer | Designation | Datasheet |
|---|---|---|
| Tung-Sol | 12BE6 | PDF (243 KB) |
| Mazda-Belvu | 12BE6 | PDF (29 KB) |
| Lorenz | HK90 | PDF (125 KB) |
Documents held here and used to write this page.
- HK90 (filed under HK90)
- OSCILLATOR CHARACTERISTICS