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| Schematic |
you can change speed by adjusting RV1
Please be careful! This circuit is directly connected with AC !
Thursday, August 23, 2012
Wednesday, August 22, 2012
LED Multivibrator
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If you want change speed of blinking then change values of C1 and C2. increased values of C1,C2 will decrease speed.
Supply Voltage 3-6V
Tuesday, August 21, 2012
LB1403 LED Sound Level Indicator Circuit
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This is a another sound level meter circuit using LB1403N. You can use this for any audio system such as Amplifier, Radio, or TV. As well as you can use this either ac level meters such as vu meters or dc level meters such as signal meters.
Features of LB1403N
- Capable of generating a bar-display for input voltage with 5 LEDs.
- Operates from either AC or DC input voltage because of on-chip rectifier amplifier.
- Lighting levels remain stable to line regulation because of on-chip voltage reference.
- LEDs are driven by a constant current; stable to line regulation.
- Power supply voltage range is wide (3.5 to 16V), for wide range of applications.
- SIP-9 pin package and fewer externally connected component result in smaller space requirements on the circuit board.
- Low noise at LED lighted mode.
For stereo audio systems you need two of this circuit and you can adjust the sound sensitivity by challenging value of RV1.You can directly connect this circuit with output of your amplifier or any other audio system.
Supply voltage for this circuit is 6-12v.
Monday, August 20, 2012
LED Knight Rider Circuits - CD4017 NE555
Everyone like to build LED Knight Rider circuits, specially beginners and little kids. So I will post some knight rider circuits and you can find different pattern of the knight rider circuit from here.
In this circuit LED is running one by one from D1 to D10. after D10, its star from D1 and this will continue until power is disconnected.
In this circuit LED is running two ways. in first step D1, D3, D5, D7 and D9 is light up one by one and the D10, D8, D6, D4 and D2 is light up one by one after D2, its star from D1 and this will continue until power is down. this is more similar to the circuit of Knight Rider TV Series. how ever this circuit doesn't display a tail like circuit in tv series. if you like to add tail then simply add capacitors between every LED. the value of capacitor depend on input voltage and type of LED. so i can't give a value for capacitor. therefor you have to chosen your own value for this by adding different capacitors from 10-220uf. however i think 47-100uf is good for this.
This is the same circuit of pattern 1 and only change the polarity of LED. after power is given all the LED s are light up except D1. next all the LED s are light up except D2. this will continue until D10 off. after that it begin with D1 and this will repeated until power is applied. This method also can applied to the pattern 2. RV1 used to change speed of scrolling. Supply Voltage is 5-12v. Change the R1 resistor to 470-1k when you used power supply above 5v.
4017 is a synchronous decimal up counter with decimal-decoder. it count when the signal is applied to the CLK (pin 14).
The NE555 is a highly stable device for generating accurate time delays or oscillation and used to generate clock pulses for 4017.
LED Knight Rider 1
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| Pattern 1 Preview |
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| Pattern 1 Circuit |
In this circuit LED is running one by one from D1 to D10. after D10, its star from D1 and this will continue until power is disconnected.
LED Knight Rider 2
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| Pattern 2 Preview |
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| Pattern 2 Circuit |
In this circuit LED is running two ways. in first step D1, D3, D5, D7 and D9 is light up one by one and the D10, D8, D6, D4 and D2 is light up one by one after D2, its star from D1 and this will continue until power is down. this is more similar to the circuit of Knight Rider TV Series. how ever this circuit doesn't display a tail like circuit in tv series. if you like to add tail then simply add capacitors between every LED. the value of capacitor depend on input voltage and type of LED. so i can't give a value for capacitor. therefor you have to chosen your own value for this by adding different capacitors from 10-220uf. however i think 47-100uf is good for this.
LED Knight Rider 3 - Shadow
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| Pattern 3 Preview |
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| Pattern 3 Circuit |
This is the same circuit of pattern 1 and only change the polarity of LED. after power is given all the LED s are light up except D1. next all the LED s are light up except D2. this will continue until D10 off. after that it begin with D1 and this will repeated until power is applied. This method also can applied to the pattern 2. RV1 used to change speed of scrolling. Supply Voltage is 5-12v. Change the R1 resistor to 470-1k when you used power supply above 5v.
4017 is a synchronous decimal up counter with decimal-decoder. it count when the signal is applied to the CLK (pin 14).
The NE555 is a highly stable device for generating accurate time delays or oscillation and used to generate clock pulses for 4017.
Saturday, August 18, 2012
7 Band Spectrum Analyzer Circuit using OP Amps
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| Spectrum Analyzer |
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| Circuit Preview |
You can use this circuit for build your own spectrum analyzer for amplifier or any audio equipments.
In this post i will not show the sound level meter circuit and this is only the circuit of the band pass filter for the analyzer. you need to connect outputs of this circuit with sound level indicator circuits such as LB1403 , AN6877 to get full circuit. you need totally 8 of sound level indicator circuits. the last bar show the sound level and if you doesn't like it you can omitted that one and then you need totally 7 of sound level indicator circuits.
For build seven band pass filter here I used LA6458S. but you can use any operational amplifier for this. If you use operational amplifier such as LM324 or TL084 then you need only two ICs for this. because those ICs include four different operational amplifiers and LA6458S include only two operational amplifiers.
By using this circuit you can be able to get 50Hz, 100Hz, 330Hz, 1kHz, 3.3kHz, 6.3kHz and 12.5kHz output and these out put can be directly connected with any audio level meter circuit mentioned earlier.
Couple of year ago I found this circuit from a radio and then I build this one and it worked great..!
Supply voltage for this circuit is 12v.
