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How about that - A crystal set with a monogram. (I hope the
S wasn't for stupid.) This is getting fun. This radio went together very quick.
Why? That is because all the major components were made in Oklahoma. All I had
to do is drill the base and wire it up.
Now is a good time to showcase some of the parts on this set. The standout
item is that cats whisker detector.
The coil has two taps. One is about 15% from the bottom and that is
where the antenna connects. The other tap is about 50% of the 240 uh coil and
that is for the detector tap. The coil is space wound for higher performance.
The radio is wired like my #55 set. The only
difference is the brass link switch to select either the detector stand or
a 1N34A diode hidden under the base. The binding posts are available
from Jon Bowers.
The base is made with white oak with a stain finish. The size is
about 11 by 7 inches (28x18 cm). I used a clear piece of plexiglas as a
panel to mount the variable capacitor. I like these old time capacitors
and this is a good way to show it off. The clear material matches the
coil form. This is about the brassiest set that I have ever built.
How does it work? It works fairly well. This circuit is prone
to a lot of nighttime shortwave interference. I sometimes put an inductor
in series with the antenna to reduce the 49 meter broadcasters. My two
capacitor, one coil sets are better for reducing the shortwave ghosts.
I like the single capacitor in this design because it is easier
to adjust that while probing around the galena for a signal. Once you
get a signal, then it is easier next time because you know where to tune.
But this is another show radio. I like to make these as they
aren't as technically demanding as my dx sets.
73 and good crystal DX. Dave - N2DS
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