We found this circuit in an old documentation, but the components used offer no difficulty in obtaining it. The CMOS integrated circuits are powered by a 6V supply.
We found this preamplifier for recording heads in a 1980s documentation. The circuit can be used...
An advanced motor control software plug-in for Microchip’s MPLAB® X Integrated Development...
This circuit is from Delco Radio found in a 1968’s documentation. The transistors are of the time...