The 812A may be used as an AF power amplifier, modulator or RF amplifier at full ratings to 30 MHz and reduced ratings to 100 MHz.
| GENERAL DESCRIPTION |
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The 812A is a high perveance, easy to drive medium-mu triode closely modeled after the original RCA design. Improvements include a low loss easy to clean ceramic base and a cermic thermal insulator under the plate cap. The 812A may be used as an AF power amplifier, modulator or RF amplifier at full ratings to 30 MHz and reduced ratings to 100 MHz. |
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| TECHNICAL SPECIFICATIONS | |
| ELECTRICAL | |
| Filament | Thoriated-tungsten |
| Voltage (AC or DC) | 6.3 ±0.3 V |
| Current | 4 A |
| Amplification factor (average) | 29 |
| Maximum frequency for full ratings | 30 MHz |
| Interelectrode capacitances Grid to filament Plate to filament Grid to plate |
5.4 pF 0.77 pF 5.5 pF |
| MECHANICAL | |
| Cooling | Convection |
| Base | Ceramic standard 4 pin |
| Socket | SK4A |
| Plate connector | PC1A or equivalent |
| Operating position | Vertical or Horizontal (pins 1 & 4 in vertical plane) |
| Maximum dimensions Diameter Length |
57 mm (2.23 in.) 166 mm (6.52 in.) |
| Net weight (average) | 113 gm (4 oz) |
| Specifications may change without notice | |
| THIS TUBE IS USED IN THE FOLLOWING SHORTWAVE BROADCAST TRANSMITTERS | ||
| Manufacturer | Transmitter specifications | Power in kW |
| THIS TUBE IS AVAILABLE FROM | ||
| Manufacturer | Rebuilder | Distributor |
| Penta Laboratories | Richardson Electronics | |
| Vacuum Tubes, Inc. | ||
| PRICE LEVEL (US$) | |||||
| 1 | 2 | 3 | 4 | 5 | 6 |
| 0 - 10 | 10 - 100 | 100 - 1000 | 1000 - 10,000 | 10,000 - 50,000 | 50,000 - 100,000 |