This is a combined circuit of tone generator and preamplifier. We found it in a 1975 documentation. Operational amplifiers of that time can be replaced by modern equivalents.
This game aims to make you discover which is the combination of activated switches that make the...
The LM109, which is not common today, was manufactured by many semiconductor companies. This...
This adapter circuit for measuring voltages was found in Radio Electronics from April 1966. The...