This circuit for automotive use was found in American documentation from the 90s. The circuit uses common components today. The relay is 12 V.
The lie detector we presented was created by a professional detective and found in a 1982...
This circuit is suitable for testing motor starting capacitors. Capacitors from 2 to 8 uF are...
This low power bass booster is from the 1977 National Semiconductor Audio Handbook. The circuit is...