Rf Power Meter Circuit

Rf decibel power meter description.

Rf power meter circuit. The circuit diagram of the decibel meter in figure 1 stands out by its simplicity which is due to the type ad8307 monolithic demodulating logarithmic amplifier ic1 from analog devices. Power can be measured in a variety of ways dependent upon the application. Adjust c1 for peak reading. This circuit is another radio frequency rf field strength meter similar with our previous field strength meter circuit but with lower supply voltage only a single cell 1 5v battery.

The cornerstone of the power meter circuit shown in figure 1 is an analog devices ad8307an logarithmic amplifier ic u1. Although you might consider the ic as slightly expensive at about 10 in single quantities its cost is justified by the wide dynamic range and outstanding accuracy offered. The measurand quantity to be measured is applied to pin 8 inp of ic1 via input socket k1 and capacitor c1. The rf power in dbm can be read directly with a multimeter and i ve found it particularly useful for measuring rf filter response when combined with a sweep generator and an oscilloscope.

A tap circuit supplements the power meter extending the upper limit by 40 db allowing measurement of up to 100 w 50 dbm. To use turn on transmitter and meter. Rf power meter pep average pulse power power measurement techniques in line power meter absorption power meters sensors. Although you might consider the.

Rf power meters or wattmeters are used for measuring power in rf circuits. Here is yet another ad8307 based rf power meter which adds an opamp to produce a dc output voltage of 1mv dbm e g 0mv 0dbm 10mv 10dbm etc.