The figure shows a way to apply gain control to the LM3600 OTA. The circuit is from a Radio Electronics from July 1988.
This alarm circuit is from a 1987 publication, however the components used are still modern. The...
In the figure we have a configuration that allows to test NPN transistors and with the addition of a...
We find this current meter circuit from 0 nA to 200 nA in a Linear Technology application manual....