Greg Pitner

  • Yes, those two tags have very similar radiation patterns.

  • The antenna on the 2100-AFR is essentially a dipole with its axis being the long side of the tag. You can get a pretty good sense of the radiation pattern by Googling “dipole antenna radiation”. But to put it in words, if you draw an imaginary line between the tag and the reader antenna, the tag radiation pattern is favorable when the line is…[Read more]

  • Hi Hunter — tags can indeed become more difficult to read if they are placed close together, and the tag density you have is in the ballpark where this can be a problem. Setting a minimum distance is tricky because it can depend on the environment, the orientation of the tags, exactly how much read degradation is tolerable, and so on. But in…[Read more]

  • In the application note you want to look for material on the “Sensor Code”. This is the value that can be used to detect moisture. It’s not called the “Moisture Code” because, strictly speaking, it changes in response to de-tuning of the tag antenna. This can be caused by moisture, but not exclusively. So the Sensor Code can indicate different…[Read more]

  • ThingMagic readers can be used with our sensors. There is sample C# code using the ThingMagic API in Application Note AN002, “Reading Magnus-S Sensors”. It’s available on the website:

    http://community.rfmicron.com/application-notes/

    The ThingMagic API supports Java as well as C#, and the relevant API calls have almost the same syntax.

  • The moisture reading won’t be in percentage form. The idea is to look for changes in the Sensor Code available from the tag and then inferring moisture from those changes. If you’re not reading the Sensor Code it’s probably because the reader isn’t looking in the right memory location, which is the Reserved Bank, word 0xB for the 2100 sensor.

  • I just posted this in response to another question, but it applies here: in general, the Sensor Code on the 2100 drops when water is on the interleaved finger structure on the tag. It’s not a calibrated measurement, in the sense of a certain volume of water being equal to a certain numerical change. But more water does tend to result in a larger c…[Read more]

  • In general, the Sensor Code on the 2100 drops when water is on the interleaved finger structure on the tag. It’s not a calibrated measurement, in the sense of a certain volume of water being equal to a certain numerical change. But more water does tend to result in a larger change in the Sensor Code in comparison to when the tag is dry.

  • Hi Martinez,

    Here is a code fragment in C# for the ThingMagic Mercury API which can control the Astra reader. This shows how to grab the Sensor Code, which is stored in the Reserved bank in word location (decimal) 11, or (hex) B.

    Reader r = Reader.Create(“tmr:///COM5”); // Assumes reader is connected on COM5 emulated serial…[Read more]