Q:

What do these deprecated markings mean?

I found this Moog Prodigy synthesizer schematic that I'm trying to figure out how it works in order to learn more about how electronics work.
What do the circled symbol at the top of the schematic mean ?
What does "N.C" mean ? An example of it is located at the far right.
What does the "*" next to R2 mean ?
What does the "1%" next to R5 mean ?
What does -9V and -12V mean ?
What does the arrow next to R14 mean ?  

A:

The item in the top left is a 2-pole switch that has 3 positions (32', 16', 8'). In the top right, NC means no connection. The 1% is the tolerance of resistor R5. R14 is a potentiometer (variable resistor).  The arrow is the wiper arm of R14. The -12V is the voltage powering that part of the circuit. The voltage (-9.0V) at the output of U2B is either for purposes of troubleshooting or for an adjustment. The meaning of the star above R2 is probably explained in a note somewhere else on the schematic.

