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Home Transmission of Signals Transmitters Measurement of Power Output  
See also: Power Amplification, Power Factor, Power Output and Plate Efficiency  
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Measurement of Power OutputAuthor: J.B. Hoag
The coupling is adjusted until the amplifier draws its rated plate current when tuned to resonance. Then the power output P, in watts, is given by P = I^{2}R, where I is the current in amperes as read on the r.f. ammeter, and R is the resistance in ohms of the noninductive resistor. Special resistors for this purpose, with resistances ranging from 73 to 600 ohms, and for power ratings up to 100 watts, can be purchased on the market. Higher power requirements can be met by the use of seriesparallel combinations of these units. For crude work, incandescent lamp bulbs may be used in place of the resistor and meter.


Home Transmission of Signals Transmitters Measurement of Power Output 