Voltase hobby

VU Meter 5 with UAA180

This circuit of measurement of level uses the UAA180 of SIEMENS and a circuit of rectification of precision, round the IC2B. The calibration has become in steps 3db from the one Led in the other, ensuring, a very good rate of precision, in the measurement of entering acoustic signals. The Led can be square, thus when they are placed the one by in the other, they give the picture of bar, without space. VU Meter 5 with UAA180 Circuit diagram: Parts List: R1= 47Kohm        
R2= 1Mohm    
R3= 33Kohm        
R4= 10Kohm        
R5= 220ohm    
R6-9=390ohm
R7=2.2K ohm    
R8-10=330Kohm    
R11=180Kohm
C1= 47uF 25V
C2-4=47nF 100V    
C3=2.2uF 25V    
D1....8= LED GREEN
D9-10= LED YELLOW
D11-12= LED RED
D13....17= 1N4148
IC1= UAA180
IC2= TL072

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