This power step drains just 3.5 mA from the battery and can provide good playback on a 4-ohm speaker. The circuit is from an 80's documentation.
The power supply shown in the figure provides voltages between 0 and approximately 15 volts, with...
Another triggered oscillator that we found in the November 1984 Radio Electronics magazine. The...
Found in a 1980s German publication, this circuit tests batteries by type. The circuit is based on a...