SC-1
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11
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31. Install C9, .001 uF (marked .001, 102, or 1 nF).
Installation of Q3 oscillator coils L1 and L2: The wiring of your SC1 is now
finished except for your own plans about how to use and tune it. If you
expect to exercise options other than our suggestions for basic shortwave
broadcast listening, read the information following the assembly directions
before proceeding. Otherwise, complete the following steps.
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32. Install L2, marked 42EB. Do not confuse it with the other shielded
coil. L2 is the coil used for tuning the lower shortwave frequency bands.
It fits the PC board holes only one way: you will notice one extra hole,
which is provided for using a crystal in place of L2 and C10.
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33. Coil L1, marked 42IF123, requires a simple modification before
installation. There is a small tubular capacitor visible in the plastic
bottom of the coil that needs to be removed, which is done by crushing it
with the tip of a small screwdriver or the point of a knife. It crumbles quite
easily and it is actually fun to be destructive for a change! Crush the
capacitor and install L1. It fits on the PC board in only one direction.
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34. The remaining three holes near L1 are for installation of a jumper
wire to determine L1's tuning range:
Jumper A to B to tune 10.7-18.3 MHz
Jumper C to B to tune 6.7-12.9 MHz
If you have little familiarity with shortwave bands, we suggest the C
to B connection to get started.
The PC board assembly of your Ramsey SC1 Shortwave Converter is now
complete. This is a good time for you or a friend to recheck your work,
retracing each of the preceding assembly steps. Watch for the quality of
solder connections and correct orientation of the three
transistors.
