Schematic Circuits ==>

Phono Preamplifier

Simple circuitry suitable for moving-magnet cartridges
Passive high-frequency equalization
Phono Preamplifier schematic

In recent years, following CD's introduction, vinyl recordings are almost disappeared. Nevertheless, a phono preamplifier is still useful for listening old vinyl discs from a well preserved collection. This simple but efficient circuit devised for cheap moving-magnet cartridges, can be used in connection with both audio power amplifiers shown in preceding pages, featuring low noise, good RIAA frequency response curve, low distortion and good high frequency transients behaviour due to passive equalization in the 1 to 20KHz range. Transistors and associated components provide ± 18V supply to the op-amp, improving headroom and maximum output voltage.

PART list

R1=47K 1/4W Resistor
R2=100R 1/4W Resistor
R3=_6K8 1/4W Resistor
R4=68K 1/4W Resistor
R5,R6=2K7 1/4W Resistor
R7=_2K2 1/4W Resistor
R8=39K 1/4W Resistor

C1-C3=100΅F 25V Electrolytic Capacitors
C4,C5=47nF 63V Polyester Capacitors 5% tolerance

D1,D2=BZX79C18 18V 500mW Zener Diodes

IC1=LM833 Low noise Dual Op-amp

Q1=BC337 45V 800mA NPN Transistor
Q2=BC327 45V 800mA PNP Transistor

J1=RCA audio input socket

Keywords : Shematic, Circuits, Audio, Phone, Telephone, Amplifier, Electronic, Amplificator
Writer : delon  |
17 Jan 2007 Wed   
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