This circuit was obtained from HAM Radio magazine in an 80's issue. The FETs are types of the time and the frequency is determined by the crystal. The circuit operates at voltages from 3 to 9 V.
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...