This circuit for the very low frequency range was found in the Radio Electronics magazine of February 1983. The components are according to the frequency range to be amplified.
Using the CA3130, this NAB EQ preamp has excellent gain. The power supply does not have to be...
Other operational amplifiers in the series, such as the MC34072, MC34074, MC35071, MC35072,...
This adjustable regulator uses the 741 and power transistors and can supply a current of up to 1...