Mounting everything on the dish
Time to assemble the handle that allows you to hold
the parabolic microphone. Figure 6-10 shows how the pieces (minus the
parabolic dish itself) go together. When these fittings are assembled on
the parabolic dish, the threads go through the hole in the center of the
dish with one gasket inside the dish and one gasket outside the dish.
1. In the sheet of gasket
material, cut a hole (using your utility knife or X-ACTO knife) large
enough to slip over the 1" threads.
Use one of the PVC fittings as a template.
2. Use scissors to cut the
outer diameter of the gasket about 3⁄8
"
larger than the inner diameter.
3. Repeat Steps 1 and 2 to create a second gasket.
Whenever you cut with a utility knife or an X-ACTO
knife, wear leather work gloves to reduce the chance of cutting yourself
if the knife slips.
4. Glue a 16", 1"-diameter PVC pipe into the female
end of the 90° fitting.
5. Glue the male end of the 90° fitting into the slip
fit end of the 1" x 1" fitting.
Gaskets 1" thread x 1" slip fitting 1" thread x ¾" slip fitting 1" x 1"
90° slip fitting 1" PVC pipe
6. Drill a 3⁄8" hole about
eight inches from the end in the side of the PVC pipe that will be to
your left when you’re holding the parabolic microphone.
You use this hole to feed the wires from the
microphone cartridge to the box containing your circuit.
7. Slip one of the gaskets over
the threads on the 1" x 3⁄4
"
fitting. Then slip the threads from the inside through the hole in the
dish.
8. Slip the other gasket over
the threads and then screw the 1" x 1" fitting onto the threads.
9. Tighten the fitting by hand so that the gaskets
are compressed a little and the dish is held securely between the
gaskets.
Figure 6-11 shows the handle assembled on the dish.
