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Desert Spider.

 OK, now I'm getting serious about building.  This is your typical loose coupled set with a few more options I built in.  I can't say the design is original by no means, What I did was take several ideas from several of the more reputable builders(Mike Peebles, Dan Petersen, Dave Schmarder) and put them together to make a really nice, versatile DXer that performs excellent.  Starting with the ATU, I used 1/4 inch thick Plexiglas and 24 Guage wire.  45 wraps gives it about 190 uH according to my LCR meter.  The capacitor is a 400pF and the DPST switch takes that capacitor from tuning the coil in parallel or putting it in series with the antenna (see schematic).  
The Main Tuning circuit uses the same spider form but 65 turns which gives it an inductance of 250uH.  I'm using the same type 400pF capacitor which is connected across the top and bottom of the main tuning coil.  You will notice two switches to the right of the capacitor.  One switch puts a 100pF capacitor in series with the variable capacitor.  Why you ask?  OK, this drops the over all capacitance across the coil and lowers the Max capacitance available.  If you were to look at a graph while the variable capacitor is spun from Max. to Min. you would notice that as you get up toward the 1000 kHz range, the frequencies start getting real close.  By adding capacitance, you spread out the tuning available on the upper end so you don't have issues getting that sweet spot or catching that hard to get station.  The other switch lets you select between the standard 1N34A germanium or a Schottky Bat Diode.  Like the knobs?  Well, I was in Iraq when I built this one too.  What I found was some PVC pluming parts that kind of fit together.  The very center is a 1" plywood plug cut from a hole saw bit and the back is also plugged with plywood.  A fresh coat of flat black paint and there you have it.  The last feature is the sliding rail system I came up with.  Can you see the two silver stiff rods?  This allows me to vary the coupling between the two without the two units getting askew. Once I get settled back in the states I plan on taking it apart and refinishing the wood