We found this circuit in an old publication. The components used are rare today. Accuracy depends on the resistors in the input selection network. The circuit operates from 10 to 500 kHz.
This high-gain digital amplifier uses general-purpose transistors. The supply voltage is logic...
We found this circuit in the March 1993 issue of Electronis Now magazine. The circuit uses common...
Using an LDR as a sensor and an operational amplifier this circuit was found in the Encyclopedia of...