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 the same way that we can regulate the voltage in the positive branch of the circuit, we can...
Based on the MC1488 or MC1489 operational amplifiers, this circuit has a 5000V isolation driving a...
Found in the July 1968 Supertena Bulletin of a Popular Electronics, this receiver makes use of the...