View single post by sparks
 Posted: Nov 7th, 2011 01:51 PM
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Joined: Jan 15th, 2008
Location: New Zealand
Posts: 77
From my experience, the raudive diode is deliberately non-resonant to avoid pickup of any specific radio station voice content, therefore allowing it to be more of a broadband noise source from which voices can be formed from. As such it is essentially a noise source generator that provides raw energy for the voice formation process. The antenna is meant to be kept very short, and adjusted in length so noise just becomes audible, but no longer, so that radio station voices are not being received.
If resonance was desired in the design, the original broadband functionality could be synthesized by choosing it to be self resonant in an unused part of the radio spectrum, say below the longwave band for instance, where atmospheric noise is quite high and no radio traffic is present of any intensity.