The purpose of this circuit is to measure the intensity of audio signals. We found it in the September 1990 issue of Radio Electronics magazine. The circuit works as a S meter.
We can implement this filter with more modern equivalent operational amplifiers, since the LM110 is...
This stethoscope or amplifier for hearing aid using a crystal headset and microphone was found in a...
The normal use of a 4520 as a divide-by-16 counter is shown in Figure bellow. In the normal...