This photo shows the stuff at the top of the mast. The suspension
web comes into the picture from the lower right; the piano wire is fastened
to it with a 6-32 screw and passes over the fulcrum. The fulcrum is a 10-32
screw with a slot filed in it. This is so that the spot where the wire leaves the fulcrum is more of
a point, rather than an area for it to slide on. This is in the hopes of reducing friction.
The wire goes back and wraps around the guitar tuner, which allows
fine adjustment of the height of the end of the boom. With all the fiddling around I did
getting it to work, the wire wound up somewhat bent, but it doesn't seem to matter much.
At the left of the photo is the heater resistor. This 2-watt resistor is used to
help stratify the air in the enclosure and reduce convection-generated noise.