/Schematics/Audio devices/Very sensitive audio amplifier

Part list

P1_____________22K   Log. Potentiometer
R1,R9__________10K   1/4W Resistors
R2______________1M   1/4W Resistor
R3______________4K7  1/4W Resistor
R4,R7_________100K   1/4W Resistor
R5______________3K9  1/4W Resistor
R6______________1K5  1/4W Resistor
R8_____________100R  1/4W Resistor
C1,C2_________100nF  63V Polyester or Ceramic Capacitors
C3,C6___________1µF  63V Polyester or Ceramic Capacitors
C4_____________10µF  25V Electrolytic Capacitor
C5____________470µF  25V Electrolytic Capacitor
D1___________1N4148  75V 150mA Diode
Q1,Q2,Q3,_____BC547  45V 100mA NPN Transistors
Q4____________BC337  45V 800mA NPN Transistor
MIC1__________Miniature electret microphone
SW1____________SPST Switch (Ganged with P1)
J1_____________Stereo 3mm. Jack socket
B1_____________1.5V Battery (AA or AAA cell etc.)

Use 32-ohm headphones. Amplifier is very sensitive and could be used for some kind of eavesping.

Author (sent by): Red circuits

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Rating: (2.82, votes 1234)


Date: 26-03-2007

Lokalna verzija ove stranice: Veoma osjetljivo audio pojačalo


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