This 1975 tachometer for cars with platinum can serve as an idea for new projects. The components are from the era and a modern equivalent operational amplifier can be used.
In this circuit we show how to configure the LM3914 as a bargraph or moving point, supplying 10...
We found this circuit in a documentation for 1977 American radio amateurs. The LM336 integrated circuit...
This modulator circuit is nothing more than an audio amplifier that serves to modulate amplitude...