| GENERAL DESCRIPTION |
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The 889-R is a three electrode tube designed specifically for use as modulator, amplifier or oscillator in radio transmitting service. The cathode is a pure-tungsten filament. The 889-R has a forced-air-cooled anode capable of dissipating 5 kW with an air flow of 500 cfm. Maximum ratings of 8.5 kVdc plate voltage and 16 kW plate input apply at frequencies up to 40 Mc. The tube is rated for service up to 100 Mc. |
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| TECHNICAL SPECIFICATIONS | |
| ELECTRICAL | |
| Filament Voltage Current Starting Current |
Tungsten 11 volts 125 amp The filament current must never exceed 187 amperes, even momentarily. |
| Amplification Factor | 21 |
| Direct Interelectrode Capacitances (Approx.) Grid to Plate Grid to Filament Plate to Filament |
18.5 μμF 23.3 μμF 3.0 μμF |
| MECHANICAL | |
| Mounting Position | Vertical only, glass end up |
| Overall Length | 11-½" ± ⅜" |
| Radiator Clamp Diameter | 10-⅞" ± ⅛" |
| Radiator | Integral part of tube |
| Bulb Temperature | 150 max. °C |
| Input Air Temperature (to Radiator) | 50 max. °C |
| Radiator Temperature | 180 max. °C |
| Specifications may change without notice | |
| THIS TUBE IS USED IN THE FOLLOWING SHORTWAVE BROADCAST TRANSMITTERS | ||
| Manufacturer | Transmitter specifications | Power in kW |
| RCA | ET-4750 | 7.5 |
| ET-7285 | 7.5 / 10 | |
| THIS TUBE IS AVAILABLE FROM | ||
| Manufacturer | Rebuilder | Distributor |
| Kennetron | Richardson Electronics | |
| 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 |