Found in a 1965 Electronic Design, this circuit generates adjustable pulses between 200 uA and 10 mA. The components admit equivalents. Pulse duration is 1 us.
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...