RF and Audio Probe (CB5912E)

Any FET can be used on this 80's circuit. Power can be supplied with batteries. The output is applied to the input of a small audio amplifier.

Comparator (CB5090E)
The HA2620 integrated circuit used in this comparator is from the 80's, but the setting can be...
Long Interval Timer LF355 (CB3996E)
This timer for long time intervals is from the 1990 Motorola Linear Databook. The setting applies...
Constant current source (CB20484E)
This circuit uses a current regulator from the 90's. This component is uncommon nowadays. The...