no stable state
one stable state
two stable state
either one or two stable states
3 to 10 volts d.c.
1 to 5 volts d.c.
-5 to +5 volts d.c.
+5 to +15 volts d.c.
sine wave oscillator
square wave oscillator
saw-tooth wave oscillator
none of the stated above
Schmmitt trigger
blocking oscillator
multivibrator
Weinbridge oscillator
amplifiers
rectifiers
oscillators
digital equipments