In the figure we have a basic PLL circuit with the LM567 or equivalent. The circuit is from a 1977 documentation.
We found this circuit in a Radio Electronics from the 90s. The circuit is for conventional analog...
The operational of this amplifier can be the 741 and the resistors R1 and R3 are of 10 k. R2B is...
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...