These 6 to 12 V source with current up to 100 mA was found in Radio Electronics magazine from June 19666. The source has a current indicator and uses transistors of the time.
This circuit was found in Electronics Now magazine and can be applied to any JFET. The circuit has high...
When this alarm is off current drained is very low, only about 60 µA. The circuit can be powered...
This circuit was published in an English magazine from 1977, but it can be easily assembled since...