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Digital Wattmeter Ranging from 300nW to 30W
The digital wattmeter project was created for the purpose of measuring power in the range of 300nW to 30W.
Some of the features that the device possess is the ability to measure power ranging from 300nW to 30W with 0-500 MHz frequency. The wattmeter can handle a maximum of 50W since it was based on a dummy load of 50 Ohms. A 2×16 character display will be used to display the measurements in Watts with the use of an EEPROM to store the displayed data. The wattmeter is very accurate, fast, and easy to construct.
Included in the circuit are AC generator and a 50 Ohm resistor. The effect of the current that flows in the circuit is easily calculated and will be consumed by the resistor where the effect is transformed into heat.
The AD8307 circuit measures the input power which is divided down to the proper range using a resistor ladder. The analog output from the AD8307 is converted by a 12-bit A/D converter to a digital number. The A/D converter will be combined with 4096 since it is 12-bit and the range of 0 to 4095 output values. The text will be fetched from memory.