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.
This amplifier, for millimeters from 0 to 1 mA, was found in a 1957 Raytheon publication. The...
This circuit was found in an old European publication, but it can be implemented with more modern...
This small FM transmitter was found in a Radio Electronics magazine in 1991. The magazine no...