The original posting describes a spectrum analyzer that shows the strength of radio-frequency signals. It's built by reprogramming a toy that uses the Texas Instruments CC1110F32 RF system-on-a-chip (http://focus.ti.com/docs/prod/folders/print/cc1110f32.html)
You (jules) are discussing a spectrometer, that shows the strength of optical spectral lines to identify materials (http://en.wikipedia.org/wiki/Spectrometer). These are two totally different things - radio-frequency vs optical. (Just want to keep the discussion from getting totally confused.) Also, Natrium == Sodium (Na)
You are completely right. Now that I'm reading it again they are repeating "radio" a lot of times and there are a ton of clues that this is radio frequency, but the picture of the device on the yellow peppers just triggered "oh they are measuring the light spectrum of yellow peppers". Sorry for the confusion.
You (jules) are discussing a spectrometer, that shows the strength of optical spectral lines to identify materials (http://en.wikipedia.org/wiki/Spectrometer). These are two totally different things - radio-frequency vs optical. (Just want to keep the discussion from getting totally confused.) Also, Natrium == Sodium (Na)