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Dummy Load

That power can be transmitted maximum, output impedance from power amplifier level of end must equal to transmission channel characteristic impedance and impedance from antenna. For the purpose is required ala at matching network to equalize impedance.

Impedance from antenna hardly depends on frequency. While impedances from transmission channel is equal to channel characteristic impedance if transmission channel length is cline gradation. So antenna and useless transmission channel as harmonic cavity reference matching network to. Instead is required a burden known by the impedance is categorically as reference (Dummy Load). which must free of influence frequency and can handle dismissal of big power (changes all powers to come to become temperature). Impedance Dummy Load is usually 50 or 75Ohm. Inductor and capacitor is component having impedance which depends on to frequency. Pure resistor is not affected by frequency, though practically resistor only have the character of resistive but having capacitive and inductive of parasite though small.

Dummy Load can be made itself with installing parallel some resistors causing is obtained resistance and power wanted. Carbon resistor and film resistor has minimum parasite inductor so that many used to make dummy load. Carbon resistor the price far obtainable and cheaper with bigger power compared to film resistor.

Parallel some resistors, besides to get big power, intended also minimizes wild inductance from the resistors. For example usable carbon resistor 300 Ohm/ 2 Watt counted 6 fruit connected in parallel, to get Dummy Load.