This circuit was found in a 73 magazine for radio amateurs from the 90s. The circuit uses high voltage transistors and the relay is high voltage as well.
This circuit was found in a 1980s documentation, using a comparator from the time. The...
Using circuits from Analog Devices, this circuit does not need a symmetrical power supply. It is...
The Sample and Hold circuit shown in the figure was found in a 1994 Linear Applications Handbook by...