Now you can “see” microwave energy in the 2.4-2.5GHz range with this fully assembled and pretested microwave detector. No batteries needed! The microwave power is harvested and rectified to create a DC voltage that powers the LED.  Use this battery free detector near your microwave oven or wireless LAN router to detect if the power level is greater than 1 milliwatt at 2.4-2.5GHz.  The LED will light up if there is wireless energy and will become brighter if the input power is increasing. When placed close to an 802.11b/g wireless LAN router the LED will flicker with the modulated signals being transmitted by the router.

This microwave detector is created from one RFD102A module, a red surface mount LED and rigid wires that make a 2.5GHz dipole antenna. This product is great for high school teachers, technology teacher, college professors, hobbyists and HAM radio enthusiasts.  The antenna can be extended with alligator clips and longer wires to detect lower frequencies. This is a great way to explore the spectrum in your area with a low cost detector.

The LED can be removed (with some good soldering skills) and wires can be soldered to the DCOUT terminal and GND that connect to a voltmeter.  With this modification the detector will detect power from 0.01mW up to 1W and will put out DC voltages from 0V to as high as 40V on an exponentially increasing scale.  This part can be a nice demonstration for the decay of power from a transmitter for an introductory microwave engineering or electromagnetics class.

You can also build your own microwave detector (RFD102A-DET) from the RFD102A module following the instructions below.  Kits are available by special request and make an excellent educational project for an introductory electronics class or for electronic hobbyists/enthusiasts.