Found in the 1969 neon lamp documentation, using neon lamps this circuit provides 18 V regulated with 0 to 4 mA current. The lamps are types of the time.
This circuit is from a 1979 publication. The sensor consists of plates or screens that, when...
The circuit is from a Radio Electronics from August 1989. The cells used at that time did not have...
The automatic modulated siren circuit shown in the figure really produces an interesting sound...