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Meet the Freedom Stik!

A contributor over at Daily KOS just discovered the Scosche series of ultra low cost FM "play with it" transmitters. Before I send you over to check it, I should give you two warnings. First, I need to warn you that the folks at Daily KOS use extremely graphic language and if that's a problem, you might not want to go there...
     The second warning is that tampering with a certified transmitter eliminates the certification. The KOS author suggests that adding a radiating element on the negative battery terminal (genius idea for more range, btw) is "still legal" and, well, er, ah, um, it's not. What that means is that certification is no longer a defense if the FCC comes by and tells you to shut it off. If you do cross paths with the FCC (and you'd be surprised what they will pursue, especially on the FM band) just do what they ask (usually 'turn it off,' in rare instances, 'give me that!')
     And speaking of the FCC, here are the cert docs from an early ver - note photos, schematic and operation page. Nice!  FCC Report on FMT-4, ID #RLQAT100
     Here's a synopses from KOS, anyway - "Meet the SCOSCHE FMT4RA Fm Transmitter. $12. Walmart auto section... I figured out that the maximum usable range for stereo music was out around 400 feet, line-of-sight, clear day. ...what if a feller were to just dangle a quarter-wavelength piece of wire from the negative-most AAA battery connection?" Answer? It works great  8^)
What if a feller were to just dangle a quarter-wavelength piece of wire from the negative-most AAA battery connection? There's two of the four wires in the 7-inch dongle (the part that hooks to your mp3 player) that, in addition to being the send or return on the audio signal, also form the (folded) driven half of an eighth-wavelength dipole. I use 107.7 mhz, so an eighth-wavelength is about 13.75 inches. Might a 14     Here's another report on the same kind of transmitter - and no graphic language.  There are 31 posts in that thread and another thread here - all good stuff.  A second follow up is posted here.
     A 5/8ths wavelength of wire attached to the negative side will work even better than the 1/4 or 1/8th wave approach the KOS contributor mentioned - a dipole does not have to be symmetrical, an unbalanced dipole will also work well.  How to calculate a 5/8 wavelength?  Use this online calculator for 5/8 wave verticals.

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