This precision bench test circuit can deliver currents in a range of 10 uA to 10 mA. The circuit is from an 80's documentation. The components are from the time.
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...