This PLL with operational amplifiers was found in 1969 documentation. The configuration can be adapted to use modern components. The circuit has a gain of 15 V / V and can operate with 10 kHz signals.
This constant current source from a 1980 publication can be used on a battery charger. Transistor Q1 may...
We found this configuration in an early 1977 publication. The PNP transistor may be the BC558 and...
This 0.5W amplifier was found in a publication of the 1980s. The output transistors can be the...