This preamplifier for phonographic capsules using FET was found in 90s American documentation. Consumption is very low. The power can be obtained from the amplifier circuit with which it works.
This circuit, suggested by National Semiconductor, provides an output voltage proportional to the...
This powerful alarm circuit was found in the July 1975 issue of Radio Electronics magazine. The...
This two-transistor circuit was found in the January 1994 issue of Electronics Now magazine....