| GENERAL DESCRIPTION |
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The 4-125A / 4D21 / 6155 / QB3/300GA / RS 1007 is a radial-beam power tetrode for use as an amplifier, oscillator, or modulator. It has a maximum plate-dissipation rating of 125 watts and a maximum plate-voltage rating of 3000 volts at frequencies up to 120 MHz. The low grid-plate capacitance of this tetrode together with its low driving-power requirement allows considerable simplification of the associated circuit and driver stage. Cooling is by radiation from the plate and by air circulation through the base and around the envelope. The 4-125A / 4D21 / 6155 / QB3/300GA / RS 1007 in class-C rf service will deliver up to 375 watts plate power output with 1.2 watts nominal driving power. |
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| TECHNICAL SPECIFICATIONS | |
| Plate Dissipation (Max.) | 125 watts |
| Screen Dissipation (Max.) | 20 watts |
| Grid Dissipation (Max.) | 5 watts |
| Frequency for Max. Ratings (CW) | 120 MHz |
| Cooling | Radiation & Forced Air |
| Filament Voltage Current |
Thoriated Tungsten 5.0 volts 6.5 amperes |
| Capacitances (Gnd. Cath. Connection) Input Output Feed-through |
10.8 pF 3.1 pF 0.05 pF |
| Amplification Factor (g1-g2) | 5.9 |
| Base | 5-Pin Special |
| Recommended Air-System Socket | SK-410 |
| Recommended Heat Dissipating Connector | HR-6 |
| Maximum Seal Temperature | 200°C |
| Maximum Envelope Temperature | 225°C |
| Maximum Length | 5.69 in; 144.50 mm |
| Maximum Diameter | 2.81 in; 71.40 mm |
| Weight (approximate) | 6.5 oz; 184.0 gm |
| Operating Position | Vertical, base up or down |
| Specifications may change without notice | |
| THIS TUBE IS USED IN THE FOLLOWING SHORTWAVE BROADCAST TRANSMITTERS | ||
| Manufacturer | Transmitter specifications | Power in kW |
| Collins | 231D-20 | 3 |
| Continental Electronics | 417 B | 50 |
| 420 A | 500 | |
| Gates | HF-5 / HF-5 B | 5 |
| HF-10 / HF-10B | 10 | |
| THIS TUBE IS AVAILABLE FROM | ||
| Manufacturer | Rebuilder | Distributor |
| Covimag | Richardson Electronics | |
| Penta Laboratories | ||
| 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 |