This little radio came out a few months ago, and is very similar to the old Radio Shack Science Fair crystal radio kit.
It has a ferrite core coil of about 400 uH, and a single gang poly film variable capacitor that measured 3-262 pF.  .  No markings on the diode, but it doesn't appear to be the usual 1N60 favored by the makers of simple kid radios.  Has coil taps for detector and antenna.   Uses the springs for making connections, and performance is nominal.  Price is about the same as the SK-103.   The plastic chassis has a clip for a 9V battery, and the manufacturer also puts out an amplified shortwave version and an amplified am broadcast band version using the same chassis.  Now for the bad news.  I bought 10 of these for use by my students at school, and ended up rejecting all but 3 of the earphones.  Also found it necessary to add a 47k resistor across the earphones, since the diode isn't quite as leaky as the 1N60.  Bottom line:  don't bother with this set until they square away their earphone quality control.  Incidentally, comparing notes with Kevin Wise, who has had students build a grunch of  the SK 103 sets as have I, we don't recall  earplug problems with any of these.  As this set looks a lot like the old RS kit, it could very well be made by the same outfit, and I did have some earplug quality problems with some of the Science Fair kits.  An added note for you Elmers out there; when you have a group of kids making radios, even if from a kit, build one yourself first, and have on hand an extra set of parts in case you turn up with missing pieces or broken parts.


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