The ETI 8140 Nude Ionization Gauge is a flange-mounted Bayard-Alpert type for the range of 1 × 10-3 to 4 × 10-10Torr. It is equipped with a bonded-thoria replaceable filament. The grid is of bifilar construction. A .005” diameter tungsten collector is provided for a low X-ray limit. The ETI 8140 is suited to either the I2R or the electron bombardment method of electrode degassing, making it compatible with either type of controller. This gauge may be baked to 450 °C.
| Connection | 2-3/4” conflat or KF 40 flange |
| Envelope | None |
| Mounting Position | Vertical |
| Collector | .005” tungsten |
| Filament | Replaceable thoria-coated iridium or dual tungsten |
| Grid | Tungsten helix configuration |
| Sensitivity for N2 | 10/Torr |
| X-ray Limit | 4 × 10-19 Torr |
| Operating Pressure | 4 × 10-10 to 1 × 10-3 Torr |
| Electron-Bombardment Degas | 70 W |
| Resistance-Heated Degas | 6.3 V to 7.5 V @ 10 A |
| Bakeout Temperature | 450 °C |