Written by: Newton C. Braga

This circuit was adapted from an Italian publication that no longer exists. This is “Onda Quadra” January 1976. The circuit for turntables with RIAA equalization can be mounted with BC548 transistors for the NPN and BC558 for PNP. The BC549 and BC559 types are low noise, and can also be used. One application is in the transition from vinyl records to other media such as, CDs and MP3. The circuit has low power consumption and can be powered by a battery of 9 V. If power supply is used, filtering must be excellent and for a stereo version can be used a single source to power the two channels. Input cables and output signals must be shielded. The level of the output signal is sufficient to excite the input of most common audio amplifiers.