This flasher circuit consists of an astable multivibrator with the frequencies given by the capacitors. The circuit is from 1965 using light bulbs, but LEDs can be used. Power comes from 4 batteries.
The inverter circuit shown in the figure can be used to power a fluorescent lamp in an emergency...
This is a combined circuit of tone generator and preamplifier. We found it in a 1975...
This circuit generates rectangular signals at a frequency determined by R2, R3, C1 and C2. See the...