These small but mighty field detectors can detect 13.56mhz signals from card readers, phones, fridges, etc.
Pair them up with the repeaters to find the optimal placement to extend your signal.
Just move the detector to the place that lights up the brightest and place the repeater in the exact same spot.
13.56mhz Field Detectors (28mm)
Rating is 5.0 out of five stars based on 4 reviews
$5.00Price
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Reviews
I found out very quickly how lucky I am that the gracious, community-minded nature of the MWG family blessed me with a 13.56 Freq Field Detector i didn't even know i wanted so badly and clearly needed much more for so many RFID projects, and NFC assessments. For practitioners' having not yet cued in The Sight with the Quickening: the 13.56khz Field Detector exposes the form of NFC reader signals and revealing strongest signal reception vectors for optimal configuration to get clean captures
This is the same size as the flexible stick on repeater stickers. It makes it super easy to figure out where to put it. Move it around until the light is the brightest. BAM, that's where your repeater sticker goes. Easy-peasy.
This field detector has become part of my EDC as I'm currently obsessed with RFID and NFC, it allows me to get a visual incite in to field locations and strengths it also make for a great visual aid in my classroom to help the students understand how these fields work.
This solved a problem I didn't even realize I had: not knowing exactly where the NFC antenna is in my phone. Take the guesswork out of placing your field repeaters and get the in the perfect spot for optimal effectiveness every time.