Music Audio Spectrum Indicator DIY Project
by ICStation in Circuits > Audio
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Music Audio Spectrum Indicator DIY Project
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FED-301K is a Audio Spectrum Indicator DIY Kit. It can display in Red/Green according to the input audio signal from microphone or AUX audio socket.It can be used to display the intensity of audio.The number of LED displayed changes according to the intensity of the audio.
Install 1pcs SMD Components TO-263 L7805 Voltage Regulator at U5
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Install 1pcs SMD components TO-263 L7805 Voltage Regulator at U5.
1.1.Randomly choose a pad on the PCB, and then melt the solder on this pad.
1.2.Use a soldering iron to melt tin on the pad just now and hold IC with tweezers in the other hand to place/press on U5 to prevent movement.
1.3.Take care to match and align each pins to pads.
1.4.Then remove soldering iron after align pins.
1.5.Then remove tweezers after solder tin cooling and solidification.
1.6.Connect others pads on STC15F104W to pads on PCB by tin and soldering iron.
Install 8pcs 10Kohm Metal Film Resistor
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Install 8pcs 10Kohm Metal Film Resistor at R1,R3,R7,R11,R2,R13,R17,R19
Install 3pcs 2Kohm Metal Film Resistor
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Install 3pcs 2Kohm Metal Film Resistor At R8,R21,R22.
Install 2pcs 470ohm Metal Film Resistor at R4,R5
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Install 2pcs 3Kohm Metal Film Resistor at R15,R16
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Install 2pcs 6.8Kohm Metal Film Resistor at R18,R20
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Install 2pcs 200Kohm Metal Film Resistor at R9,R10
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Install 2pcs 1Mohm Metal Film Resistor at R2,R6
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Install 1pcs 10ohm Metal Film Resistor at R14
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Install 1pcs 100ohm Metal Film Resistor at R23
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Install 2pcs DO-35 1N4148 Diode at D2,D3
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.The Black Mark Is Negative Pole And Connect To Mark On PCB
Install 1pcs DO-41 1N4007 Diode at D4
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The black mark is negative pole and connect to mark on PCB.
Install 10pcs 0.1uF 104 Ceramic Capacitor
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Install 10pcs 0.1uF 104 Ceramic Capacitor At C1,C2,C8-C10,C16,C18-C21
Install 1pcs DIP-18 LM3914 Operational Amplifier at U1,U2
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There is a mark on one end of IC and there is a mark on PCB where IC can place on.These two marks are corresponding to each other and are used to specify the installation direction of IC.
Install 1pcs DIP-16 CD4053 Logic IC at U4 by the Same Methods
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Install 1pcs DIP-8 NE555 Timer at U3 by the Same Methods
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Install 2pcs DC Power Socket at CN1,CN2
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It Is Recommended To Use Metal Wire Which From The Cut Resistor Metal Pin To Fix The Black Socket.
Install 1pcs 1uF Electrolytic Capacitor at C6
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Install 1pcs 1uF Electrolytic Capacitor at C6 and it is placed horizontally on the PCB. The Longer pin is positive pole that inserted into the rectangular pad.
Install 2pcs 2.2uF Electrolytic Capacitor at C3,C5
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Install 2pcs 100uF Electrolytic Capacitor at C13,C14
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Install 1pcs 47uF 25V Electrolytic Capacitor at C17
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Install 2pcs 10uF Electrolytic Capacitor at C4,C7
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Install 1pcs 5Pin 3.5mm Audio Socket at JK1
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Install 1pcs 9*7mm Microphone at MIC1
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The Marked Pin Is Negative Pole.
Install 1pcs 100Kohm Potentiometer at VR1
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Install 2pcs S8050 Transistor Transistor at Q1,Q2
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Install 1pcs S8550 Transistor Transistor at Q3
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Install 1pcs XH2.54-2P White Socket at CN3
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Identify the Pins and Installation Direction of the LED.
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The Shortest Pin Is Inserted Into Pad G.
Install 40pcs 5mm Red/Green Dual Color LED at LED1-LED40
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Done! Test
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There are three work power supply input terminals: two DC3.5mm socket and one XH2.54-2P white socket. User can use any one of them. Note: DC3.5mm socket need connect 5V and white socket need connect to DC 6V-24V.
It can start working after connected power. The LED will start working when playing music into the microphone.
Rotating potentiometer can be used to adjust the sensitivity of LED.
AUX audio socket also can input audio signal and then LED will flashing with input audio signal.
AUX audio socket has a higher priority than MIC, so it work with AUX audio if both AUX audio and MIC get signal.