Found in a 1980s telecommunications documentation, the circuit presented acts as a product detector. The modulator or mixer in the square may be that of the previous circuit.
This oscillator takes advantage of the inductance of a high impedance magnetic earphone to...
The transducer used in this configuration that appears elsewhere on this site is a piezoelectric...
November 2016 - Mouser Electronics has in stock the Toshiba Bluetooth TC35670 and 35675...