This circuit is from a 1992 PE Hobbyst Handbook. The circuit fires an old electronic flash using an SCR. The circuit can be adapted for other types of applications.
The figure shows how to implement an alarm buzzer in an LM3914 to warn about crossing the scale...
This circuit can act as a shield being controlled by a microcontroller by pin 1 or 2. The...
This circuit was obtained from a 1980's QST magazine. The circuit can generate 1 to 15 MHz signals...